gallium-ga-68-dotatate and Neuroendocrine-Tumors

Recently, advancement of somatostatin receptor (SSTR) imaging and theragnostic approach using peptide receptor radionuclide therapy (PRRT) have changed the paradigm of diagnosis and management of neuroendocrine tumor. 68Ga-DOTATATE PET/CT can diagnose the lung carcinoids with high SSTR expression. With combination of 68Ga-DOTATATE PET/CT and 18F-FDG PET/CT, tumor heterogeneity of lung carcinoid can be identified, which may guide optimal patient selection for PRRT. PRRT may be an effective and safe treatment of advanced lung carcinoids during progression with first-line somatostatin analog therapy. This review provides updates on the diagnosis and management of lung carcinoids, focusing on SSTR imaging and PRRT.

Topics: Carcinoid Tumor; Humans; Lung; Lung Neoplasms; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Positron-Emission Tomography; Radioisotopes; Receptors, Somatostatin

Gastroenteropancreatic neuroendocrine tumors(NETs), which arise from the small intestine, rectum, colon, appendix, or pancreas, have variable malignant potential with clinical behavior determined by proliferative activity according to the Ki-67 index and tumor differentiation. Somatostatin receptor (SSTR) expression by NETs allows SSTR imaging using 68Ga-DOTATATE PET/computed tomography (CT) and treatment with octreotide or SSTR-targeted peptide receptor radionuclide therapy (PRRT). 68Ga-DOTATATE PET/CT is indicated for localization of the primary tumor in select cases, staging patients with known NET, and selecting patients for PRRT. NCCN guidelines consider imaging with 68Ga-DOTATATE PET/CT appropriate for staging and receptor status assessment.

Topics: Humans; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Tomography, X-Ray Computed

Ectopic adrenocorticotropic hormone (ACTH)-secreting tumors are commonly small, yet they often lead to fulminant forms of Cushing syndrome. High-resolution functional imaging modalities, such as [Ga]-DOTATATE, have been recently introduced in clinical practice for the identification of neuroendocrine tumors. In this review, we focus on the performance of [Ga]-DOTATATE as a tool for localizing primary and metastatic sources of ectopic Cushing syndrome (ECS).. Prompt surgical removal of ectopic ACTH-secreting tumors is the mainstay of therapy in patients with ECS. Detecting such tumors with conventional cross-sectional imaging is often unsuccessful, owing to their small size. [Ga]-DOTATATE has been approved in 2016 by the Federal Drug Administration for imaging well differentiated neuroendocrine tumors. Data regarding the performance of [Ga]-DOTATATE for detecting ectopic ACTH-secreting tumors remain limited, in part owing to the recent introduction of this imaging modality in clinical practice, and in part because of the low prevalence of ECS. Nevertheless, [Ga]-DOTATATE has been reported to be useful in identifying primary and metastatic ectopic ACTH-secreting lesions that were not apparent on other imaging studies, impacting the clinical care of many patients with ECS.. [Ga]-DOTATATE-based imaging, which targets the somatostatin receptors abundantly expressed in neuroendocrine tumors, has generally high, although variable resolution in detecting the source(s) of ECS.

Topics: Cushing Syndrome; Gallium Radioisotopes; Humans; Multimodal Imaging; Neuroendocrine Tumors; Organometallic Compounds; Radionuclide Imaging; Receptors, Somatostatin

Topics: Child; Contrast Media; Humans; Multimodal Imaging; Neuroblastoma; Neuroendocrine Tumors; Octreotide; Organometallic Compounds; Radiopharmaceuticals; Receptors, Somatostatin; Sensitivity and Specificity

Neuroendocrine tumors (NETs) constitute a variety of neoplastic entities and exhibit variable degrees of neuroendocrine differentiation and phenotypes, as well as genetic profiles. Ga-DOTATATE PET is a novel imaging technique for NET. Although PET/CT is commonly utilized for oncologic imaging, PET/MRI is particularly suited for NETs, as MRI provides greater soft tissue contrast than CT, allowing for improved detection and characterization of NETs, particularly when liver metastasis is suspected or needs to be ruled out. The current pictorial review aims to illustrate the complementary advantages, as well as pitfalls of Ga-DOTATATE PET/MRI in the evaluation of NETs.

Topics: Humans; Magnetic Resonance Imaging; Multimodal Imaging; Neuroendocrine Tumors; Organometallic Compounds; Positron-Emission Tomography

This article discusses the application of fludeoxyglucose PET/computed tomography (CT) technology in head and neck cancer diagnosis and management, as well as advantages and disadvantages relative to traditional imaging modalities. A successful scan relies on precise patient preparation, and compliance to specific protocols before and during the scan. Finally, this article briefly introduces a PET/CT scan recently approved by the Food and Drug Administration for neuroendocrine tumors.

Topics: Fluorodeoxyglucose F18; Head and Neck Neoplasms; Humans; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Radioactive Tracers; Radiopharmaceuticals; Sensitivity and Specificity; Tomography, X-Ray Computed

Pancreatic Neuroendocrine Tumors (PNETs) are rare neoplasms, sporadic or familial, even being part of a syndrome. Their diagnosis is based on symptoms, hormonal disorders or may be fortuitous. The role of Nuclear Medicine is important, mainly because of the possibility of a theranostic strategy. This approach is allowed by the availability of biochemical agents, which may be labeled with radionuclides suitable for diagnostic or therapeutic purposes, showing almost identical pharmacokinetics. The major role for radiopharmaceuticals is connected with radiolabeled Somatostatin Analogues (SSA), since somatostatin receptors are highly expressed on some of the neoplastic cell types.. Nowadays, in the category of radiolabeled SSA, although 111In-pentetreotide, firstly commercially proposed, is still used, the best choice for diagnosis is related to the so called DOTAPET radiotracers labeled with 68-Gallium (Ga), such as 68Ga-DOTATATE, 68Ga-DOTANOC, and 68Ga-DOTATOC. More recently, labeling with 64-Copper (Cu) (64Cu-DOTATATE) has also been proposed. In this review, we discuss the clinical interest of a SAA (Tektrotyd©) radiolabeled with 99mTc, a gamma emitter with better characteristics, with respect to 111Indium, radiolabeling Octreoscan ©. By comparing both pharmacokinetics and pharmacodynamics of Octreoscan©, Tektrotyd© and PET DOTA-peptides, on the basis of literature data and of our own experience, we tried to highlight these topics to stimulate further studies, individuating actual clinical indications for all of these radiotracers.. In our opinion, Tektrotyd© could already find its applicative dimension in the daily practice of NETs, either pancreatic or not, at least in centers without a PET/CT or a 68Ga generator. Because of wider availability, a lower cost, and a longer decay, compared with respect to peptides labeled with 68Ga, it could be also proposed, in a theranostic context, for a dosimetry evaluation of patients undergoing Peptide Receptor Radionuclide Therapy (PRRT), and for non-oncologic indications of radiolabelled SSA. In this direction, and for a more rigorous cost/effective evaluation, more precisely individuating its clinical role, further studies are needed.

Topics: Animals; Gamma Rays; Humans; Mice; Neuroendocrine Tumors; Octreotide; Organometallic Compounds; Organotechnetium Compounds; Pancreatic Neoplasms; Peptides; Positron Emission Tomography Computed Tomography; Positron-Emission Tomography; Radioisotopes; Radiopharmaceuticals; Somatostatin; Technetium

Intrapancreatic accessory spleen (IPAS) is an uncommon finding of pancreatic mass. Differential diagnosis with pancreatic tumor, especially with non-functional neuroendocrine tumor (NF-NET), may be very hard and sometimes it entails unnecessary surgery. A combination of CT scan, MRI, and nuclear medicine can confirm the diagnosis of IPAS. 68-Ga-Dotatoc PET/CT is the gold standard in NET diagnosis and it can allow to distinguish between IPAS and NET.. A 69-year-old man was admitted to our hospital for an incidental nodule in the tail of the pancreas with focal uptake of 68-Ga-dotatate at PET/CT. NET was suspected and open distal splenopancreatectomy was performed. Pathologic examination revealed an IPAS.. This is the second IPAS case in which a positive 68Ga-Dotatoc uptake led to a false diagnosis of pancreatic NET. Here is a proposal of a literature review.

Topics: Aged; Diagnosis, Differential; False Positive Reactions; Humans; Male; Neuroendocrine Tumors; Organometallic Compounds; Pancreatectomy; Pancreatic Diseases; Positron Emission Tomography Computed Tomography; Prognosis; Splenectomy; Splenic Diseases

Neuroendocrine tumors (NETs) are rare neoplasms that emerge mainly from the GI tract, pancreas and respiratory tract. The incidence of NETs has increased more than sixfold in the last decades. NETs typically express somatostatin receptors on their cell surface, which can be targeted by 'cold' somatostatin analogs for therapy or by 'hot' radiolabeled somatostatin analogs for tumor localization and treatment. 68-Gallium-DOTA peptides (DOTATATE, DOTATOC, DOTANOC) positron emission tomography/computed tomography is a highly accurate imaging modality for NETs that has been found to be more sensitive for NET detection than other imaging modalities. In the current review, we will discuss the clinical utility of 68-Gallium-DOTATATE positron emission tomography/computed tomography for the diagnosis and management of patients with NETs.

Topics: Gastrointestinal Tract; Humans; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Prognosis

In-111 pentetreotide (Octreoscan) is a radiolabeled somatostatin analog with high binding affinity to somatostatin receptors (SSTR) used in somatostatin receptor scintigraphy (SRS). Pentetreotide labelled with In-111 is widely used due to its high affinity to SSTR 2 and 5. SSTR are expressed on neuroendocrine cells as well as several non-neural and non-endocrine cells with varying levels of density. We retrospectively reviewed articles and publications related to octreoscan accumulation in sites that classically do not have high concentrations of SSTR as well as in organs and tissues from diseases which are not usually diagnosed by octreoscan. The significance of a positive uptake as assessed by octreoscan in non-somatostatin receptor related diseases is not fully understood yet. Localization of octreotide in non-oncological disease states such as inflammation is due to presence of SSTR in activated immunological cells, over-expression by activated cells in the respective tissue and SSTR expression by blood vessels. In granulomatous diseases, over-expression of SSTR2 preferential binding sites were detected in epitheloid and giant cells. The purpose of the current study is to identify octreoscan localization in non-somatostatin receptor related disease sites to better understand the mechanism of this nonspecific accumulation which may help expand the clinical utilization of functional imaging utilizing somatostatin receptor scintigraphy in diagnosis and perhaps therapy.

Topics: Humans; Neuroendocrine Tumors; Organometallic Compounds; Radionuclide Imaging; Receptors, Somatostatin; Somatostatin

Although Somastostatin (SS) scintigraphy (SRS) has been introduced many years ago, it remains the most diffuse radionuclide diagnostic tool in patients with neuroendocrine tumours (NETs). Being SS receptors (SSTR) expressed in the majority of NETs, radiolabeled SS analogues (SS-A) provide high diagnostic accuracy, mainly in patients with gastro-entero-pancreatic (GEP) tumors. SSTR are the best target for radiotracers used either for diagnostic and therapeutic purposes in NETs due to their presence on the surface of neoplastic cells of clinical interest. 111In- DTPA-octreotide (111In-Pentetreotide, Octreoscan®), may detect either primitive or secondary lesions in the presence of a satisfactory lesion/background ratio. The unsatisfactory diagnostic performance of 18F-Fluorodeoxyglucose (18F-FDG), in NETs stimulated the synthesis of more specific positron-emitting tracers and SS-A labeled with 68Gallium (DOTA-peptides) represent actually the best radionuclide procedure for NET imaging. Alternative radiotracers, labeled either with gamma or positron emitters and showing different uptake mechanisms, as 18F-DOPA (Fluorine- 18-L-dihydroxyphenylalanine), have also been proposed and clinically utilized. Octreoscan®, despite its limitations, continue to represent the most frequently used method in evaluating the response to treatment and in follow-up of patients with NET, although the better diagnostic accuracy of DOTA-peptides.

Topics: Dihydroxyphenylalanine; Fluorodeoxyglucose F18; Humans; Neuroendocrine Tumors; Nuclear Medicine; Octreotide; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Radiopharmaceuticals; Somatostatin

Choline (CH) positron emission tomography (PET)/computed tomography (CT) with fluorine 18 (F) CH is increasingly used not only to evaluate patients with biochemically recurrent prostate cancer but also to assess metastatic lesions that are difficult or impossible to identify using more conventional modalities. Our experience with CH PET/CT has shown that it can also be used for many other malignancies.. A 71-year-old male with a neuroendocrine tumor (NET) of unknown origin showed osteoblastic bone metastases positive to F-CH PET.. Diffuse bone and liver metastases were gallium-DOTATOC PET-positive with only mild uptake on FDG PET/CT. An increased prostate specific antigen (8 μg/L) gave rise to a suspicion of concurrent prostate cancer and the patient underwent F-CH PET/CT which showed diffuse uptake in the bone. A CT-guided bone biopsy confirmed osteoblastic bone metastases from NET.. Given the aggressiveness of the tumor, the patient underwent treatment with temozolomide from July 2015 to December 2015, maintaining stable disease. However, progression was documented in January 2016 and the patient was enrolled onto a phase II peptide receptor radionuclide therapy retreatment trial, which is currently ongoing.. Our study highlights that NETs should be taken into consideration in the differential diagnosis of osteoblastic bone metastases showing F-CH uptake. A prognostic role for this imaging technique can also be hypothesized.

Topics: Aged; Bone Neoplasms; Choline; Humans; Ilium; Male; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography

Most neuroendocrine tumours (NETs) metastasize to the liver, lymph nodes and, although less frequently, to the bone. The heart is a rare localization for NET metastases.. With the introduction of the Ga-DOTATATE PET/computed tomography (CT) in our hospital as a new diagnostic method for imaging neuroendocrine tumours, more rare metastatic localizations are being found. We present six cases of patients with cardiac NET metastases detected by Ga-DOTATATE PET/CT. Also, a review of literature is presented on case reports of cardiac NET metastases in patients detected by somatostatin receptor imaging, including In-Pentetreotide single photon emission computed tomography/CT, Ga-DOTATATE PET/CT, Ga-DOTANOC PET/CT or Ga-DOTATOC PET/CT.. Most patients with cardiac NET metastases have extensive metastatic disease. The cardiac metastases are often asymptomatic.

Topics: Adult; Aged; Female; Heart Neoplasms; Humans; Male; Middle Aged; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography

Neuroendocrine tumors (NETs) are uncommon tumors with increasing incidence and prevalence. Current reports suggest that (68)Ga-DOTATATE PET/CT imaging improves diagnosis and staging of NETs compared with (111)In-DTPA-octreotide and conventional imaging. We performed a systematic review of (68)Ga-DOTATATE for safety and efficacy compared with octreotide and conventional imaging to determine whether available evidence supports U.S. Food and Drug Administration approval.. Medline, EMBASE, Web of Science, and Cochrane Reviews electronic databases were searched from January 1999 to September 2015. Results were restricted to human studies comparing diagnostic accuracy of (68)Ga-DOTATATE with octreotide or conventional imaging for pulmonary or gastroenteropancreatic NET and for human studies reporting safety/toxicity for (68)Ga-DOTATATE with 10 subjects or more thought to have NETs. Direct communication with corresponding authors was attempted to obtain missing information. Abstracts meeting eligibility criteria were collected by a research librarian and assembled for reviewers; 2 reviewers independently determined whether or not to include each abstract. If either reviewer chose inclusion, the abstract was accepted for review.. Database and bibliography searches yielded 2,479 articles, of which 42 were eligible. Three studies compared the 2 radiopharmaceuticals in the same patient, finding (68)Ga-DOTATATE to be more sensitive than octreotide. Nine studies compared (68)Ga-DOTATATE with conventional imaging. (68)Ga-DOTATATE estimated sensitivity, 90.9% (95% confidence interval, 81.4%-96.4%), and specificity, 90.6% (95% confidence interval, 77.8%-96.1%), were high. Five studies were retained for safety reporting only. Report of harm possibly related to (68)Ga-DOTATATE was rare (6 of 974), and no study reported major toxicity or safety issues.. No direct comparison of octreotide and (68)Ga-DOTATATE imaging for diagnosis and staging in an unbiased population of NETs has been published. Available information in the peer-reviewed literature regarding diagnostic efficacy and safety supports the use of (68)Ga-DOTATATE for imaging of NETs where it is available.

Topics: Humans; Intestinal Neoplasms; Lung Neoplasms; Neuroendocrine Tumors; Octreotide; Organometallic Compounds; Pancreatic Neoplasms; Pentetic Acid; Positron Emission Tomography Computed Tomography; Stomach Neoplasms

Neuroendocrine tumors are increasingly diagnosed, either incidentally as part of screening processes, or for symptoms, which have commonly been mistaken for other disorders initially. The diagnostic workup to characterize tumor behaviour and prognosis focuses on histologic, anatomic, and functional imaging assessments. Several therapeutic options exist for patients ranging from curative and debulking surgery through to liver-directed therapies and systemic treatments. Multimodal therapies are often required over the patient's disease history. The management paradigm can be complex but should be focused on curative resections and then on controlling symptoms and limiting disease progression. There are several new systemic therapies that have completed phase 3 studies with new compounds being studied in phase 2. Genetic and epigenetic markers may lead to a new era of personalised therapy in the future.

Topics: Antineoplastic Agents; Antineoplastic Agents, Hormonal; Chromogranin A; Digestive System Surgical Procedures; Embolization, Therapeutic; Fluorodeoxyglucose F18; Gallium Radioisotopes; Gastrointestinal Neoplasms; Hepatic Artery; Humans; Hydroxyindoleacetic Acid; Liver Neoplasms; Magnetic Resonance Imaging; Malignant Carcinoid Syndrome; Metastasectomy; Neoplasm Staging; Neuroendocrine Tumors; Octreotide; Organometallic Compounds; Pancreatic Neoplasms; Positron Emission Tomography Computed Tomography; Radiopharmaceuticals; Receptors, Somatostatin; Serotonin; Tomography, X-Ray Computed

Gallium-68 somatostatin receptor positron emission tomography (PET) has been used in the diagnosis of neuroendocrine tumors (NETs). The compounds often used in molecular imaging of NETs with PET are 68Ga-DOTATOC, 68Ga-DOTATATE, and 68Ga-DOTANOC. There is varying affinity to different somatostatin receptors.. To systematically review and perform a meta-analysis of published data regarding the diagnostic role of 68Ga-DOTATOC and 68Ga-DOTATATE PET in the diagnosis of NETs.. A comprehensive literature search of studies published through 30 April 2013 regarding 68Ga-DOTATOC and 68Ga-DOTATATE PET in the diagnosis of NETs was performed using the PubMed/MEDLINE, Embase, and Scopus databases. Pooled sensitivity and specificity of 68Ga-DOTATOC and 68Ga-DOTATATE PET in the diagnosis of NETs were calculated. The area under the receiver-operating characteristic (ROC) curve was calculated to measure the accuracy of 68Ga-DOTATOC and 68Ga-DOTATATE PET in the diagnosis of NETs.. Ten studies comprising 416 patients with NETs were included in this meta-analysis. The pooled sensitivity of 68Ga-DOTATOC and 68Ga-DOTATATE PET in the diagnosis of NETs calculated on a per-patient-based analysis was 93% (95% confidence interval [CI] 89-96%) and 96% (95% CI 91-99%). The pooled specificity of 68Ga-DOTATOC and 68Ga-DOTATATE PET in diagnosing NETs was 85% (95% CI 74-93%) and 100% (95% CI 82-100%). The area under the ROC curve of 68Ga-DOTATOC and 68Ga-DOTATATE PET was 0.96 and 0.98, respectively, on a per-patient-based analysis.. The molecular imaging agents 68Ga-DOTATOC and 68Ga-DOTATATE demonstrated high sensitivity and specificity in the diagnosis of NETs on PET scan. Although both are accurate tools in the diagnosis of NETs, 68Ga-DOTATATE PET may be more sensitive and specific than 68Ga-DOTATOC PET scan.

Topics: Humans; Neuroendocrine Tumors; Organometallic Compounds; Positron-Emission Tomography

Neuroendocrine tumors are malignant solid tumors originating from neuroendocrine cells dispersed throughout the body. Differentiated neuroendocrine tumors overexpress somatostatin receptors (SSTRs), which enable the diagnosis using radiolabeled somatostatin analogues. Internalization and retention within the tumor cell are important for peptide receptor radionuclide therapy using the same peptide. The use of the same DOTA-peptide for SSTR PET/CT using (68)Ga and for peptide receptor radionuclide therapy using therapeutic radionuclides like (177)Lu and (90)Y offers a unique theranostic advantage.

Topics: Fluorodeoxyglucose F18; Gallium Radioisotopes; Humans; Multimodal Imaging; Neuroendocrine Tumors; Octreotide; Organometallic Compounds; Patient Selection; Positron-Emission Tomography; Precision Medicine; Radiopharmaceuticals; Receptors, Somatostatin; Tomography, X-Ray Computed

Peptide receptor radionuclide therapy involves selective targeting of neuroendocrine tumors through the somatostatin receptors, the aim being to increase radiation dose to the tumors and spare the normal tissue. The advantage of this internal radiation therapy is the ability to selectively target multiple metastases throughout the body. Early and accurate assessment of therapy response helps not only to identify the poor responders but also to personalize the treatment regimes with the aim of achieving maximum treatment benefit. This is the basis of theranostics.

Topics: Fluorodeoxyglucose F18; Gallium Radioisotopes; Humans; Multimodal Imaging; Neuroendocrine Tumors; Organometallic Compounds; Positron-Emission Tomography; Radiopharmaceuticals; Receptors, Somatostatin; Tomography, X-Ray Computed

This review compiles and analyzes the available dosimetry data of [(68)Ga] labeled compounds. Dosimetry data are given for [(68)Ga]DOTA-NOC, TOC, TATE, and NODAGA-RGDyK. The number of PET-scans with [(68)Ga]DOTA-compounds for imaging neuroendocrine tumors is increasing because [(68)Ga] has a higher affinity to somatostatin receptors (SSTR) in comparison to comparable [(111)In]-compounds. In addition, the better image resolution of the PET images provides improved diagnostics. Despite its widespread use literature on dosimetry of [(68)Ga]-labeled radiopharmaceuticals is sparse. In some cases the description of the underlying methodology is missing or human data are gained from the extrapolation of animal experiments. More and better documented dosimetry data will further promote the use of these promising new agents.

Topics: Gallium Radioisotopes; Humans; Neuroendocrine Tumors; Octreotide; Organometallic Compounds; Positron-Emission Tomography; Radiometry; Radiopharmaceuticals

In this review we give an overview of current knowledge of (68)Ga-labeled pharmaceuticals, with focus on imaging receptor-mediated processes. A major advantage of a (68)Ge/(68)Ga generator is its continuous source of (68)Ga, independently from an on-site cyclotron. The increase in knowledge of purification and concentration of the eluate and the complex ligand chemistry has led to (68)Ga-labeled pharmaceuticals with major clinical impact. (68)Ga-labeled pharmaceuticals have the potential to cover all today's clinical options with (99m)Tc, with the concordant higher resolution of positron emission tomography (PET) in comparison with single photon emission computed tomography. (68)Ga-labeled analogs of octreotide, such as DOTATOC, DOTANOC, and DOTA-TATE, are in clinical application in nuclear medicine, and these analogs are now the most frequently applied of all (68)Ga-labeled pharmaceuticals. All the above-mentioned items in favor of successful application of (68)Ga-labeled radiopharmaceuticals for imaging in patients are strong arguments for the development of a (68)Ge/(68)Ga generator with Marketing Authorization and thus to provide pharmaceutical grade eluate. Moreover, now not one United States Food and Drug Administration-approved or European Medicines Agency-approved (68)Ga-radiopharmaceutical is available. As soon as these are achieved, a whole new radiopharmacy providing PET radiopharmaceuticals might develop.

Topics: Forecasting; Gallium Radioisotopes; Humans; Molecular Structure; Neuroendocrine Tumors; Octreotide; Organometallic Compounds; Peptides; Positron-Emission Tomography; Radioactivity; Radionuclide Generators; Radiopharmaceuticals; United States

A prospective clinical trial evaluated the effect of Ga-DOTATOC positron emission tomography-computerized axial tomography (PET-CT) on change in management of patients with lung, pancreatic, and small bowel neuroendocrine tumors. The primary eligibility criterion was a histologically proven tumor with positive somatostatin receptor subtype 2A immunohistochemistry. The primary and secondary end points were change in patient management and safety.. Referring physicians completed questionnaires pre- and post-Ga-DOTATOC PET-CT, stating current and planned patient management, respectively, with tumor board adjudication of final management decisions. Change in management was categorized as follows: no change; minor change (additional imaging, supportive care); or major change (octreotide/lanreotide therapy, tumor biopsy, surgery, peptide receptor radiotherapy, chemotherapy, biological therapy, liver embolization).. A major change in management was recommended for 54 (47.37%) of 114 subjects and a minor change for 6 (5.26%) of 114 subjects, with no change for 54 (47.37%) of 114 subjects. Grade 1 adverse events were observed in 26 of 114 subjects (nausea, headache, back pain, diarrhea); one grade 2 (petechiae) and one grade 3 (abdominal pain) adverse event were observed. No grade 2 or 3 adverse events were related to study drug and none required intervention.. Imaging with Ga-DOTATOC PET-CT has a significant impact on management of patients with neuroendocrine tumors.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Child; Child, Preschool; Female; Humans; Infant; Intestinal Neoplasms; Male; Middle Aged; Neuroendocrine Tumors; Organometallic Compounds; Outcome Assessment, Health Care; Pancreatic Neoplasms; Positron Emission Tomography Computed Tomography; Prospective Studies; Young Adult

The presence of somatostatin receptors in neuroendocrine tumors allows visualization with radiolabeled somatostatin analogs in vivo. The aim of this prospective study was to compare somatostatin receptor imaging using Tc-HYNICTOC with Ga-DOTATATE (DOTA-DPhe1,Tyr3-octreotate) with respect to sensitivity, specificity, and impact upon clinical decision making.. Sixty-eight patients (30 men, 38 women; aged 56.4 ± 13.5 years) with disseminated, histologically proven neuroendocrine tumor were enrolled. All patients with previous Tc-HYNICTOC (Tektrotyd; POLATOM, Otwock, Poland) underwent Ga-DOTATATE PET/CT. Both examinations were compared on a per-patient and per-lesion basis.. The sensitivity, specificity, positive and negative predictive values, and accuracy of Ga-DOTATATE and Tc-HYNICTOC were 100% versus 82%, 85% versus 69%, 97% versus 92%, 100% versus 47%, and 97% versus 79%, respectively.Concordant results were observed in 58 patients (49/68 positive on both Ga-DOTATATE and Tc-HYNICTOC and 9/68 negative in both examinations). Ten of 68 patients had Ga-DOTATATE-positive, Tc-HYNICTOC-negative studies. Two hundred eighteen lesions were detected using Tc-HYNICTOC, compared with 546 lesions using Ga-DOTATATE (P < 0.0001). Ga-DOTATATE detected a higher number of lesions in bone and lymph nodes, liver, intestine, and pancreas and had a higher sensitivity for subcentimeter abnormalities than Tc-HYNICTOC. Ga-DOTATATE led to management change in 23 (34%) of 68 patients.. Ga-DOTATATE has a higher sensitivity than Tc-HYNICTOC for the detection of neuroendocrine tumors. Ga-DOTATATE proved superior to Tc-HYNICTOC in detecting subcentimeter skeletal, lymph node, and liver metastases. Ga-DOTATATE PET/CT changed clinical decision making in one third of patients.

Topics: Adult; Female; Humans; Male; Middle Aged; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Prospective Studies; Receptors, Somatostatin; Sensitivity and Specificity; Single Photon Emission Computed Tomography Computed Tomography; Technetium Compounds

To analyze the biodistribution of Ga-DOTA-TATE in the normal tissues and uptake in benign, indeterminate, and malignant lesions in a population of patients with known neuroendocrine tumors (NET) using semiquantitative standardized uptake values (SUV) measurements.. One hundred four consecutively scanned patients (51 men and 53 women; mean age, 56.4 years) with confirmed diagnosis of NET underwent PET/CT 1 hour after administration of Ga-DOTA-TATE. SUVmean, and SUVmax were measured in 37 normal anatomical structures for each patient. Abnormal uptake was divided into benign, indeterminate, and malignant categories based on imaging characteristic, clinical follow-up, and pathology.. High physiologic uptake (SUVmax > 7) was observed in spleen, renal parenchyma, adrenal glands, pituitary gland, stomach, and liver (in decreasing order). Moderate uptake (3.5-7) was present in the prostate, jejunum, pancreas, ileum, and salivary glands. Mild uptake (2-3.5) was present in the uterus, colon, thyroid, rectum, and skeleton. A total of 678 lesions (limited to 5 lesions with highest uptake per organ) were included in the analysis, including 127 benign and 54 indeterminate lesions. Uptake was significantly higher in malignant lesions than in benign lesions, but an overlap was noted between the groups.. Ga-DOTA TATE uptake in normal and abnormal structures is highly variable in patients with NET. SUV is a useful measure for characterizing benign versus malignant lesions. Anatomical and clinical correlation may be necessary to characterize foci of intermediate uptake.

Topics: Adult; Aged; Aged, 80 and over; Biological Transport; Female; Humans; Male; Middle Aged; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Tissue Distribution

Quantitative imaging and dosimetry are crucial for individualized treatment during peptide receptor radionuclide therapy (PRRT). (177)Lu-DOTATATE and (68)Ga-DOTATOC/(68)Ga-DOTATATE are used, respectively, for PRRT and PET examinations targeting somatostatin receptors (SSTRs) in patients affected by neuroendocrine tumors. The aim of the study was to quantitatively and qualitatively compare the performance of (68)Ga-DOTATOC and (68)Ga-DOTATATE in the context of subsequent PRRT with (177)Lu-DOTATATE under standardized conditions in the same patient as well as to investigate the sufficiency of standardized uptake value (SUV) for estimation of SSTR expression.. Ten patients with metastatic neuroendocrine tumors underwent one 45-min dynamic and 3 whole-body PET/CT examinations at 1, 2, and 3 h after injection with both tracers. The number of detected lesions, SUVs in lesions and normal tissue, total functional tumor volume, and SSTR volume (functional tumor volume multiplied by mean SUV) were investigated for each time point. Net uptake rate (Ki) was calculated according to the Patlak method for 3 tumors per patient.. There were no significant differences in lesion count, lesion SUV, Ki, functional tumor volume, or SSTR volume between (68)Ga-DOTATOC and (68)Ga-DOTATATE at any time point. The detection rate was similar, although with differences for single lesions in occasional patients. For healthy organs, marginally higher uptake of (68)Ga-DOTATATE was observed in kidneys, bone marrow, and liver at 1 h. (68)Ga-DOTATOC uptake was higher in mediastinal blood pool at the 1-h time point (P = 0.018). The tumor-to-liver ratio was marginally higher for (68)Ga-DOTATOC at the 3-h time point (P = 0.037). Blood clearance was fast and similar for both tracers. SUV did not correlate with Ki linearly and achieved saturation for a Ki of greater than 0.2 mL/cm(3)/min, corresponding to an SUV of more than 25.. (68)Ga-DOTATOC and (68)Ga-DOTATATE are suited equally well for staging and patient selection for PRRT with (177)Lu-DOTATATE. However, the slight difference in the healthy organ distribution and excretion may render (68)Ga-DOTATATE preferable. SUV did not correlate linearly with Ki and thus may not reflect the SSTR density accurately at its higher values, whereas Ki might be the outcome measure of choice for quantification of SSTR density and assessment of treatment outcome.

Topics: Adult; Aged; Female; Humans; Liver; Male; Middle Aged; Neoplasm Metastasis; Neoplasm Staging; Neuroendocrine Tumors; Octreotide; Organometallic Compounds; Positron-Emission Tomography; Quality Control; Radiation Dosage; Radiometry; Reproducibility of Results; Sensitivity and Specificity; Time Factors; Tomography, X-Ray Computed; Treatment Outcome; Whole Body Imaging

Somatostatin receptor PET tracers such as [(68)Ga-DOTA,1-Nal(3)]-octreotide ((68)Ga-DOTANOC) and [(68)Ga-DOTA,Tyr(3)]-octreotate ((68)Ga-DOTATATE) have shown promising results in patients with neuroendocrine tumors, with a higher lesion detection rate than is achieved with (18)F-fluorodihydroxyphenyl-l-alanine PET, somatostatin receptor SPECT, CT, or MR imaging. (68)Ga-DOTANOC has high affinity for somatostatin receptor subtypes 2, 3, and 5 (sst2,3,5). It has a wider receptor binding profile than (68)Ga-DOTATATE, which is sst2-selective. The wider receptor binding profile might be advantageous for imaging because neuroendocrine tumors express different subtypes of somatostatin receptors. The goal of this study was to prospectively compare (68)Ga-DOTANOC and (68)Ga-DOTATATE PET/CT in the same patients with gastroenteropancreatic neuroendocrine tumors (GEP-NETs) and to evaluate the clinical impact of (68)Ga-DOTANOC PET/CT.. Eighteen patients with biopsy-proven GEP-NETs were evaluated with (68)Ga-DOTANOC and (68)Ga-DOTATATE using a randomized crossover design. Labeling of DOTANOC and DOTATATE with (68)Ga was standardized using a fully automated synthesis device. PET/CT findings were compared with 3-phase CT scans and in some patients with MR imaging, (18)F-FDG PET/CT, and histology. Uptake in organs and tumor lesions was quantified and compared by calculation of maximum standardized uptake values (SUVmax) using volume computer-assisted reading.. Histology revealed low-grade GEP-NETs (G1) in 4 patients, intermediate grade (G2) in 7, and high grade (G3) in 7. (68)Ga-DOTANOC and (68)Ga-DOTATATE were false-negative in only 1 of 18 patients. In total, 248 lesions were confirmed by cross-sectional and PET imaging. The lesion-based sensitivity of (68)Ga-DOTANOC PET was 93.5%, compared with 85.5% for (68)Ga-DOTATATE PET (P = 0.005). The better performance of (68)Ga-DOTANOC PET is attributed mainly to the significantly higher detection rate of liver metastases rather than tumor differentiation grade. Multivariate analysis revealed significantly higher SUVmax in G1 tumors than in G3 tumors (P = 0.009). This finding was less pronounced with (68)Ga-DOTANOC (P > 0.001). Altogether, (68)Ga-DOTANOC changed treatment in 3 of 18 patients (17%).. The sst2,3,5-specific radiotracer (68)Ga-DOTANOC detected significantly more lesions than the sst2-specific radiotracer (68)Ga-DOTATATE in our patients with GEP-NETs. The clinical relevance of this finding has to be proven in larger studies.

Topics: Adult; Aged; Aged, 80 and over; Cross-Over Studies; Digestive System Neoplasms; Female; Gallium Radioisotopes; Humans; Male; Middle Aged; Multimodal Imaging; Neuroendocrine Tumors; Organometallic Compounds; Positron-Emission Tomography; Prospective Studies; Radiopharmaceuticals; Receptors, Somatostatin; Tomography, X-Ray Computed

We hypothesized that (68)Ga-DOTATATE uptake of neuroendocrine tumors is sensitive to therapy with a nonradioactive somatostatin analog.. (68)Ga-DOTATATE PET/CT was used to examine 105 patients, 35 of whom had been pretreated with long-acting octreotide. The maximum standardized uptake value (SUV(max)) of target tissues, as well as metastases, was compared between the groups of patients with (group 1) and without (group 2) octreotide treatment.. The SUV(max) of the spleen and liver was significantly lower in group 1 than in group 2 (both P < 0.001). There were no significant group differences in SUV(max) for primary tumors (28.6 ± 6.8 vs. 32.9 ± 31.5) or metastases in the liver (27.2 ± 14.8 vs. 25.7 ± 10.7), lymph nodes (41.4 ± 19.5 vs. 25.0 ± 6.3), or skeleton (39.5 ± 22.0 vs. 15.4 ± 7.8). In 9 patients available for intraindividual comparison, tumor uptake was unaffected by treatment with somatostatin analogs (21.7 vs. 20.6; P = 0.93).. Treatment with a long-acting somatostatin analog did not significantly reduce (68)Ga-DOTATATE binding in neuroendocrine tumors but tended to improve the tumor-to-background ratio.

Topics: Adult; Aged; Aged, 80 and over; Biological Transport; Female; Humans; Male; Middle Aged; Multimodal Imaging; Neoplasm Metastasis; Neuroendocrine Tumors; Octreotide; Organometallic Compounds; Positron-Emission Tomography; Tomography, X-Ray Computed; Young Adult

Radiolabeled somatostatin analogs represent valuable tools for both in vivo diagnosis and therapy of neuroendocrine tumors (NETs) because of the frequent tumoral overexpression of somatostatin receptors (sst). The 2 compounds most often used in functional imaging with PET are (68)Ga-DOTATATE and (68)Ga-DOTATOC. Both ligands share a quite similar sst binding profile. However, the in vitro affinity of (68)Ga-DOTATATE in binding the sst subtype 2 (sst2) is approximately 10-fold higher than that of (68)Ga-DOTATOC. This difference may affect their efficiency in the detection of NET lesions because it is the sst2 that is predominantly overexpressed in NET. We thus compared the diagnostic value of PET/CT with both radiolabeled somatostatin analogs ((68)Ga-DOTATATE and (68)Ga-DOTATOC) in the same NET patients.. Forty patients with metastatic NETs underwent (68)Ga-DOTATOC and (68)Ga-DOTATATE PET/CT as part of the work-up before prospective peptide receptor radionuclide therapy. The performance of both imaging methods was analyzed and compared for the detection of individual lesions per patient and for 8 defined body regions. A region was regarded positive if at least 1 lesion was detected in that region. In addition, radiopeptide uptake in terms of the maximal standardized uptake value (SUVmax) was compared for concordant lesions and renal parenchyma.. Seventy-eight regions were found positive with (68)Ga-DOTATATE versus 79 regions with (68)Ga-DOTATOC (not significant). Overall, however, significantly fewer lesions were detected with (68)Ga-DOTATATE than with (68)Ga-DOTATOC (254 vs. 262, P < 0.05). Mean (68)Ga-DOTATATE SUVmax across all lesions was significantly lower than (68)Ga-DOTATOC (16.0 ± 10.8 vs. 20.4 ± 14.7, P < 0.01). Mean SUVmax for renal parenchyma was not significantly different between (68)Ga-DOTATATE and (68)Ga-DOTATOC (12.7 ± 3.0 vs. 13.2 ± 3.3).. (68)Ga-DOTATOC and (68)Ga-DOTATATE possess a comparable diagnostic accuracy for the detection of NET lesions, with (68)Ga-DOTATOC having a potential advantage. The approximately 10-fold higher affinity for the sst2 of (68)Ga-DOTATATE does not prove to be clinically relevant. Quite unexpectedly, SUVmax of (68)Ga-DOTATOC scans tended to be higher than their (68)Ga-DOTATATE counterparts.

Topics: Adult; Aged; Aged, 80 and over; Biological Transport; Female; Humans; Male; Middle Aged; Multimodal Imaging; Neoplasm Metastasis; Neuroendocrine Tumors; Octreotide; Organometallic Compounds; Positron-Emission Tomography; Tomography, X-Ray Computed

This study assessed: 1) the clinical efficacy of imaging with 68Ga-DOTATATE PET/CT (SSTR (somatostatin receptor)-PET) to detect medullary thyroid carcinoma (MTC); and 2) the therapeutic efficacy of peptide receptor radionuclide therapy (PRRT) with 177Lu-DOTATATE in MTC patients.. Patients with histologically proven MTC and suspected recurrence following thyroidectomy, based on raised serum calcitonin levels, underwent SSTR-PET. In addition, to evaluate the clinical efficacy and safety of PRRT, the patients with intense uptake on SSTR-PET or 99mTc-octreotide scintigraphy underwent PRRT. The Common Terminology Criteria for Adverse Events (version 4.03) was used to grade adverse events after PRRT. Treatment response was classified as complete response (CR), partial response (PR), stable disease (SD), and progressive disease (PD).. Twenty MTC patients (10 male, 10 female) with a median age of 48.5 years underwent SSTR-PET. SSTR-PET was positive in 17/20 patients (85%). Four of the 17 patients with positive SSTR-PET were scheduled for PRRT. In addition, 2 patients had positive 99mTc-octreotide scintigraphy results (Krenning score ≥ 2) and were scheduled for PRRT. Two of the 6 patients who underwent PRRT showed PR, 2 SD and 2 PD. Two patients died during the follow-up period. Median overall survival was 19 months (95% CI: 5.52-29.48). There were no cases of significant toxicity.. Radiolabeled somatostatin analogs are contributive for the management of recurrent MTC. 68Ga-DOTATAE PET-CT showed a relatively high detection rate in recurrent MTC. In addition, PRRT with 177Lu-DOTATATE was found to be a safe alternative therapeutic option for MTC.

Topics: Feasibility Studies; Female; Humans; Male; Middle Aged; Neoplasm Recurrence, Local; Neuroendocrine Tumors; Octreotide; Positron Emission Tomography Computed Tomography; Precision Medicine; Radioisotopes; Receptors, Somatostatin; Thyroid Neoplasms

A 58-year-old man who underwent surgery for a well-differentiated neuroendocrine tumor of pancreatic origin was evaluated with 68Ga-DOTATATE PET/CT imaging in the follow-up period. After PET/CT findings consistent with disease remission, the patient was started on leflunomide treatment with the diagnosis of rheumatoid arthritis. The patient received leflunomide for 6 months. Then, 68Ga-DOTATATE PET/CT scan was repeated to evaluate the primary disease outcome. Besides the disease remission, we also observed alterations in DOTATATE uptakes of some tissues and organs. In this case, we present the changes in 68Ga-DOTATATE PET/CT scan findings after leflunomide use.

Topics: Humans; Leflunomide; Male; Middle Aged; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Tissue Distribution

A 54-year-old man with metastatic well-differentiated neuroendocrine tumor of the pancreas underwent 68Ga-DOTATATE PET/CT scan to evaluate treatment response. Patient was known for remote history of chronic lymphocytic leukemia (CLL), previously treated. Scan revealed diffusely increased abnormal tracer uptake throughout the marrow of the axial and proximal appendicular skeleton. Bone marrow biopsy revealed relapsed CLL. We present a rare case of relapsed CLL incidentally detected on 68Ga-DOTATATE PET/CT.

Topics: Humans; Leukemia, Lymphocytic, Chronic, B-Cell; Male; Middle Aged; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography

Recognition of pseudoprogression in malignant glioma is one of the major challenges in the Response Assessment in Neuro-Oncology criteria. Somatostatin receptors were overexpressed on the surface of the most high-grade glioma. The corresponding PET imaging is used for planning radiation and radionuclide therapy. However, the heterogeneity of somatostatin receptors distribution is mainly responsible for the lack of specificity. Here we reported a case of a 35-year-old man with mesenchymal oligodendroglioma operation and radiotherapy 19 months ago. 68 Ga-DOTATATE PET showed intense uptake near the operation region, which has been misinterpreted as tumor recurrence.

Topics: Adult; Glioma; Humans; Male; Neoplasm Recurrence, Local; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Receptors, Somatostatin

Pretreatment predictions of absorbed doses can be especially valuable for patient selection and dosimetry-guided individualization of radiopharmaceutical therapy. Our goal was to build regression models using pretherapy 68Ga-DOTATATE PET uptake data and other baseline clinical factors/biomarkers to predict renal absorbed dose delivered by 177Lu-DOTATATE peptide receptor radionuclide therapy (177Lu-PRRT) for neuroendocrine tumors. We explore the combination of biomarkers and 68Ga PET uptake metrics, hypothesizing that they will improve predictive power over univariable regression.. Pretherapy 68Ga-DOTATATE PET/CTs were analyzed for 25 patients (50 kidneys) who also underwent quantitative 177Lu SPECT/CT imaging at approximately 4, 24, 96, and 168 hours after cycle 1 of 177Lu-PRRT. Kidneys were contoured on the CT of the PET/CT and SPECT/CT using validated deep learning-based tools. Dosimetry was performed by coupling the multi-time point SPECT/CT images with an in-house Monte Carlo code. Pretherapy renal PET SUV metrics, activity concentration per injected activity (Bq/mL/MBq), and other baseline clinical factors/biomarkers were investigated as predictors of the 177Lu SPECT/CT-derived mean absorbed dose per injected activity to the kidneys using univariable and bivariable models. Leave-one-out cross-validation (LOOCV) was used to estimate model performance using root mean squared error and absolute percent error in predicted renal absorbed dose including mean absolute percent error (MAPE) and associated standard deviation (SD).. The median therapy-delivered renal dose was 0.5 Gy/GBq (range, 0.2-1.0 Gy/GBq). In LOOCV of univariable models, PET uptake (Bq/mL/MBq) performs best with MAPE of 18.0% (SD = 13.3%), and estimated glomerular filtration rate (eGFR) gives an MAPE of 28.5% (SD = 19.2%). Bivariable regression with both PET uptake and eGFR gives LOOCV MAPE of 17.3% (SD = 11.8%), indicating minimal improvement over univariable models.. Pretherapy 68Ga-DOTATATE PET renal uptake can be used to predict post-177Lu-PRRT SPECT-derived mean absorbed dose to the kidneys with accuracy within 18%, on average. Compared with PET uptake alone, including eGFR in the same model to account for patient-specific kinetics did not improve predictive power. Following further validation of these preliminary findings in an independent cohort, predictions using renal PET uptake can be used in the clinic for patient selection and individualization of treatment before initiating the first cycle of PRRT.

Topics: Biomarkers; Humans; Kidney; Neuroendocrine Tumors; Octreotide; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Precision Medicine

The present study aimed to compare the efficacy of 68Ga-DOTATATE PET/CT and 18F-FDG PET/CT imaging in the diagnosis, staging, and prognosis evaluation of neuroendocrine tumors (NET). A total of 55 patients (43 were initially evaluated, 12 were evaluated after treatment) who underwent fluorine-18 labeled fluorodeoxyglucose (18F-FDG) and 68Ga DOTATE PET/CT examinations were reviewed retrospectively, and the pathological data were collected. In the initial evaluation, 27/43 were pathologically confirmed as NET patients, as detected by gallium-68 labeld 1, 4, 7, 10-tetraazacyclododecane-1, 4, 7, 10-tetraaceticacid-D-Phel-Tyr3-Thr8-OC; among them, 23 were correctly detected by 18F-FDG. In lesion-based comparison, 119/168 focal lesions were depicted on 18F-FDG PET/CT and 68Ga-DOTATATE PET/CT, respectively (P = .0363). Strikingly, gallium-68 labeld 1, 4, 7, 10-tetraazacyclododecane-1, 4, 7, 10-tetraaceticacid-D-Phel-Tyr3-Thr8-OC had higher maximum standard uptake value than 18F-FDG but was negatively related to the NET grade for the former, while the latter was positively related to the NET. The value of 68Ga-DOTATATE PET/CT in the diagnosis and staging of NET is higher than that of 18F-FDG PET/CT in NETs, while the value of 18F-FDG PET/CT cannot be ignored in the NET. The combined application of the 2 tracers has major clinical significance in the management of patients with NET.

Topics: Fluorodeoxyglucose F18; Humans; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Positron-Emission Tomography; Retrospective Studies

Cardiac metastases are an infrequent site of metastasis in neuroendocrine tumors, and the treatment implications in the era of peptide receptor radionuclide therapy (PRRT) are unclear. Potential safety concerns exist regarding cardiac integrity and function in response to PRRT. We describe our institutional experience with 4 patients with well-differentiated, midgut neuroendocrine tumors with cardiac involvement detected on Ga-DOTATATE PET/CT scans who were treated with PRRT.

Topics: Female; Heart Neoplasms; Humans; Male; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Receptors, Peptide

Topics: Aged, 80 and over; Asymptomatic Infections; Child, Preschool; China; COVID-19; COVID-19 Nucleic Acid Testing; Edetic Acid; Female; Gallium Isotopes; Gallium Radioisotopes; Humans; Hypoglycemia; Incidental Findings; Male; Neuroendocrine Tumors; Oligopeptides; Organometallic Compounds; Polymerase Chain Reaction; Positron Emission Tomography Computed Tomography; Prostatic Neoplasms; Radiography, Thoracic; Sensitivity and Specificity

68Ga-FAPI (fibroblast activation protein-specific inhibitor) PET/CT was performed in a 56-year-old man with multiple liver masses, which were confirmed grade 2 well-differentiated neuroendocrine tumors with liver Tru-Cut biopsy. With 68Ga-DOTATE PET/CT, primary tumor in the pancreas, multiple metastases in the liver and metastatic portocaval lymph node were detected. In 68Ga-FAPI PET/CT imaging performed for comparison, it was seen that metastatic lesions in the liver were distinguished much better because of low background activity, and the primary tumor and metastatic lymph node were clearly selected. This case suggested that FAPI-bounded radionuclides may be useful in the evaluation and targeted therapy of neuroendocrine tumors.

Topics: Biopsy; Humans; Male; Middle Aged; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Quinolines

In this manuscript, we describe a rare case of neuroendocrine tumour metastatic to the testicle, presenting with testicular mass as an isolated symptom. We describe the investigations and management leading us to this uncommon histological diagnosis and explore its significance and impact on further management.

Topics: Colectomy; Humans; Male; Middle Aged; Neuroendocrine Tumors; Orchiectomy; Organometallic Compounds; Positron-Emission Tomography; Testicular Neoplasms; Testis; Ultrasonography

Neuroendocrine tumors (NETs) of the esophagus are extremely rare and aggressive and have a poor prognosis. Because most esophageal cancers occur in the middle and lower parts of the esophagus, cervical esophageal NETs are even rarer. Herein, we present 68Ga-DOTATATE PET/CT findings in a 37-year-old woman who was diagnosed with cervical esophageal NET.

Topics: Adult; Esophageal Neoplasms; Female; Humans; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography

Leptomeningeal metastasis is the metastatic spread of the disease to leptomeninges from solid tumors such as breast, lung cancer, and melanoma. Cauda equine syndrome is a neurological condition caused by compression of the cauda equine. The incidence of large cell neuroendocrine carcinoma in resected lung cancers appears to be 2.1% and 3.5%. The incidence of clinically diagnosed leptomeningeal metastasis in patients with solid tumors is approximately 5%. Here, we present cauda equine syndrome caused by the metastasis of large cell neuroendocrine carcinoma detected by 18F-FDG PET/CT and also 68Ga-DOTATATE PET/CT.

Topics: Cauda Equina Syndrome; Female; Fluorodeoxyglucose F18; Humans; Lung Neoplasms; Male; Meningeal Neoplasms; Middle Aged; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography

68Ga-DOTATATE PET/CT is an important tool for imaging neuroendocrine tumors, including skeletal metastases. However, false-positive results can occur in inflammatory pathologies such as sacral insufficiency fracture. We report the case of a 47-year-old man who was diagnosed with a neuroendocrine tumor of the pancreas. 68Ga-DOTATATE PET/CT showed 68Ga-DOTATATE uptake at the right side of the sacrum. Afterward, MRI made the diagnosis of sacral insufficiency fracture.

Topics: Fractures, Stress; Humans; Male; Middle Aged; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Sacrum

68Ga-DOTATATE PET is becoming a popular imaging technique for detecting neuroendocrine tumors (NETs). The sensitivity and specificity of 68Ga-DOTATATE PET compared to standard cross-sectional imaging with triple phase CT or MRI with Eovist has not been studied extensively.. 68Ga-DOTATATE PET scans ordered at our institution between 11/2017 and 7/2018 were reviewed. Patients with evidence of liver metastases were sorted and cross-sectional imaging results were reviewed. Specifically, the number of lesions detected by standard cross-sectional imaging versus 68Ga-DOTATATE PET was compared.. 32 patients with 68Ga-DOTATATE PET scans and a corresponding MRI or CT were identified. Primary tumors were pancreatic (43.8%), small bowel (25%), hepatic (9.4%), gastric (6.3%), appendiceal (3.1%), and not localized (12.5%). 26/32 (81%) patients had CT scans and 17/32 (53%) had MRI scans. 25/32 (78%) patients had at least equal or increased number of lesions identified on 68Ga-DOTATATE PET when compared with CT or MRI. 7/32 (21.9%) had fewer lesions on 68Ga-DOTATATE PET compared to CT or MRI. However, 3 of these cases had numerous liver lesions. The overall sensitivity and specificity of 68Ga-DOTATATE PET are 92.9% and 75% respectively.. 68Ga-DOTATATE PET appears to have superior sensitivity in detecting metastatic NET to the liver. Further studies are needed to determine if it should be considered the test of choice for evaluating patients with metastatic NET to the liver. While standard cross-sectional imaging will be needed for surgical planning, 68Ga-DOTATATE PET will identify lesions that may not be seen on other imaging modalities.

Topics: Humans; Liver Neoplasms; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Positron-Emission Tomography

The importance of 68Ga-DOTATATE PET/CT in the evaluation of neuroendocrine tumors is well established. However, false-positive results can occur due to inflammatory pathologies. We report a 47-year-old man who was diagnosed with a neuroendocrine tumor of the stomach. Initial 68Ga-DOTATATE PET/CT showed intense 68Ga-DOTATATE uptake in the petrous apex. Histopathological confirmation could not be obtained, thus the asymptomatic patient was followed with periodic clinical/radiologic examinations for more than 2.5 years. Therefore, this lesion was diagnosed as a cholesterol granuloma of the temporal bone. These results suggested that an initial wait-and-scan approach is a feasible management strategy for similar presentations.

Topics: Cholesterol; Granuloma; Humans; Male; Middle Aged; Neuroendocrine Tumors; Organometallic Compounds; Petrous Bone; Positron Emission Tomography Computed Tomography

A 56-year-old woman presented with right iliac fossa pain. Abdominal CT showed a mesenteric mass in the right iliac fossa, adjacent to the vena cava inferior and right ureter. Biopsy of the mass revealed a well-differentiated neuroendocrine tumor. 68Ga-DOTATATE PET/CT showed strong somatostatin receptor expression only within in a small, central area of this mesenteric mass, with faint 68Ga-DOTATATE uptake in the majority of this mesenteric mass. Pathology revealed an IgG4-positive storiform fibrosis surrounding a mesenteric adenopathy. 68Ga-DOTATATE PET/CT discriminates between neuroendocrine tumor lymph node metastases and fibrosis, hereby avoiding potential sampling error of tumor biopsies and guiding surgical approach.

Topics: Female; Fibrosis; Humans; Immunoglobulin G; Lymphatic Metastasis; Middle Aged; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography

A 69-year-old man with history of metastatic neuroendocrine tumor presented for initial staging with 68Ga-DOTATE PET/CT. 68Ga-DOTATATE PET/CT showed incidental focal increased DOTATATE uptake in the left apical prostate tissue, which was thought to be of benign etiology. Digital rectal examination later was consistent with a palpable nodule along with elevated prostate-specific antigen of 7.0 ng/mL. MRI of prostate demonstrated a 3.8-cm lesion followed by a targeted biopsy that revealed prostatic acinar adenocarcinoma. Chronic inflammatory cell infiltrates were also noted on biopsy, and this may have been the cause of increased DOTATATE uptake seen on 68Ga-DOTATATE PET/CT study.

Topics: Aged; Biological Transport; Biopsy; Carcinoma, Acinar Cell; Humans; Incidental Findings; Liver Neoplasms; Male; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Prostate; Prostatic Neoplasms

A 52-year-old man with newly diagnosed gastric neuroendocrine tumor (NET) underwent 68Ga-NODAGA-JR11 and 68Ga-DOTATATE imaging. 68Ga-DOTATATE PET/CT showed no 68Ga-DOTATATE uptake in the lesion, where 68Ga-NODAGA-JR11 showed intense uptake. The patient subsequently received endoscopic submucosal dissection and en bloc resection of the lesion, which was pathologically confirmed as gastric NET (G2). The positive findings of 68Ga-NODAGA-JR11 in the current case highlighted that 68Ga-NODAGA-JR11 PET/CT may be a promising molecular imaging technique for the detection of NETs with high sensitivity.

Topics: Acetates; Heterocyclic Compounds, 1-Ring; Humans; Male; Middle Aged; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography

Carcinoma of breast with neuroendocrine differentiation is an extremely rare entity, especially in male population. Although the "garden variety" of male breast cancers is often metastatic at presentation, with an aggressive course, there is hardly any literature about neuroendocrine variants. We report a case of a 57-year-old man who had pituitary symptoms, which on 68Ga-DOTANOC PET/CT imaging turned out to be a metastatic lesion, with somatostatin expressing primary in breast and other sites, with histopathological confirmation of neuroendocrine differentiation in breast cancer.

Topics: Breast Neoplasms; Humans; Male; Middle Aged; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography

Studies have demonstrated that positron emission tomography/computed tomography (PET/CT) with Gallium-68 (68Ga)-labeled somatostatin analogues are effective at detecting metastatic disease in neuroendocrine tumors (NET), especially extrahepatic metastases. However, PET in combination with full-dose contrast-enhanced CT (ceCT) exposes patients to higher radiation (~25 mSv). The use of non-contrast-enhanced low-dose CT (ldCT) can reduce radiation to about 10 mSv and may avoid contrast-induced side effects. This study seeks to determine whether ceCT could be omitted from NET assessments.. We retrospectively compared the performance of PET/ldCT versus PET/ceCT in 54 patients (26 male, 28 female) who had undergone a 68Ga-DOTATATE PET/CT. The selection criteria were as follows: available ldCT and ceCT, histologically confirmed NET, and follow-up of at least 6 months (median, 12.6 months; range, 6.1-23.2 months). The PET/ldCT and PET/ceCT images were analyzed separately. We reviewed metastases in the lungs, bones, and lymph nodes. The results were compared with the reference standard (clinical follow-up data).. The PET/ceCT scans detected 139 true-positive bone lesions compared with 140 lesions detected by the PET/ldCT scans, 106 true-positive lymph node metastases (PET/ceCT) compared with 90 metastases detected by the PET/ldCT scans, and 26 true-positive lung lesions (PET/ceCT) compared with 6 lesions detected by the PET/ldCT scans. The overall lesion-based sensitivity for full-dose PET/ceCT was 97%, specificity 86%, negative predictive value (NPV) 93%, and positive predictive value (PPV) 93%. The overall lesion-based sensitivity for PET/ldCT was 85%, specificity 73%, NPV 72%, and PPV 85%.. This study presents the first evidence that ceCT should not be omitted from extrahepatic staging using 68Ga-DOTATATE PET/CT in patients with NET. ceCT alone can be used as a follow-up to reduce radiation exposure when the patient has already undergone PET/ceCT and suffers from non-DOTATATE-avid NET.

Topics: Female; Gallium Radioisotopes; Humans; Male; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Positron-Emission Tomography; Retrospective Studies; Tomography, X-Ray Computed

One of the primary prerequisites for peptide receptor radionuclide therapy (PRRT) in patients with neuroendocrine tumors (NET) is the presence of somatostatin receptors (SSTR) on NET cells. NET are highly heterogeneous and an individual patient as well as separate metastases can harbor cells with different clones, which influence the SSTR expression on NET cells. With this background we looked into our institutional database to assess the prognostic significance of quality of SSTR expression on SSTR PET/CT imaging in patients treated with at least two cycles of Lu-177 DOTATOC or Lu-177 DOTATATE.. Clinical reports and images from 65 (25 females, 40 males; 65 ± 11 years old) patients with progressive grade 1 or grade 2 NET with 2-5 therapy cycles of PRRT with an average administered dose of 6.6 ± 0.97 GBq Lu-177 DOTATOC or Lu-177 DOTATATE were analyzed. All patients were examined with baseline Ga-68 DOTATATE or Ga-68 DOTATOC PET/CT (PET). Quality of SSTR expression as a measure of heterogeneity on indexed lesions was assessed visually. Patients were followed for a median duration of 25 months after the first PRRT (range 5-77 months).. A total of 70% of the patients received three or more therapy cycles. Twenty-six patients (40%) were treated with PRRT as first or second line while 39 (60%) as third line or more. SSTR expression was heterogeneous in 28 (44.4%) and homogeneous in 35 (55.6%) patients. Disease stabilization could be achieved in 23 patients (35.4%), whereas 17 (26.1%) showed partial remission and 25 patients (38.5%) had disease progression. Median OS was not reached. The 24-month survival rate of the whole study cohort was 83%. In univariate analyses, factors influencing OS were carcinoid heart disease, carcinoid syndrome and quality of SSTR expression (p < 0.05). Patients with heterogeneous SSTR expression on target lesions had a significantly lower OS (p = 0.01). Median time to progression in total patient population was found to be 40 months. Patients with heterogeneous SSTR expression on target lesions had significantly lower TTP (26 months vs 54 months log Rank p = 0.013). By multivariate analyses, quality of SSTR was found to be the only prognostic factor for OS (p = 0.04; HR = 3.68) and also for TTP (p = 0.03; HR = 3.09).. Visual assessment of SSTR heterogeneity has both predictive and prognostic value in progressive grade 1 or grade 2 NET patients undergoing PRRT.

Topics: Aged; Female; Humans; Male; Middle Aged; Neuroendocrine Tumors; Octreotide; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Prognosis; Radioisotopes; Receptors, Somatostatin

Topics: Abdominal Pain; Biopsy; Diagnosis, Differential; Humans; Intestinal Neoplasms; Lymph Nodes; Lymphatic Metastasis; Male; Mesenteric Artery, Superior; Mesenteric Veins; Mesentery; Middle Aged; Neuroendocrine Tumors; Organometallic Compounds; Panniculitis, Peritoneal; Peritoneal Neoplasms; Radionuclide Imaging; Tomography, X-Ray Computed; Weight Loss

Neuroendocrine tumors are found throughout the body, including the pancreas. These tumors are phenotypically and genetically heterogeneous and can be difficult to accurately image using current imaging standards. However, positron emission tomography/computed tomography with radiolabeled somatostatin analogs has shown clinical success because many neuroendocrine tumors overexpress somatostatin receptor subtype 2. Unfortunately, patients with poorly differentiated neuroendocrine tumors often have a diminished level of somatostatin receptor subtype 2. We found that histone deacetylase inhibitors can upregulate the functional expression of somatostatin receptor subtype 2.. We evaluated the effect of histone deacetylase inhibitors on somatostatin receptor subtype 2 expression at the mRNA and protein level in neuroendocrine tumor cell lines. The effect of histone deacetylase inhibitors on surface somatostatin receptor subtype 2 was also investigated by fluorescence-activated cell sorting analysis. Changes in somatostatin receptor subtype 2 expression in neuroendocrine tumor xenografts after treatment were imaged using Ga68-DOTATATE positron emission tomography/computed tomography.. The functional increase of somatostatin receptor subtype 2 in neuroendocrine tumors after histone deacetylase inhibitor treatment was confirmed through in vitro experiments and small animal Ga68-DOTATATE positron emission tomography/computed tomography imaging. Histone deacetylase inhibitors increased somatostatin receptor subtype 2 transcription and protein expression in neuroendocrine tumor cell lines. Small animal Ga68-DOTATATE positron emission tomography/computed tomography imaging confirmed the enhancement of radiopeptide uptake after histone deacetylase inhibitor administration.. This study demonstrates a new method to potentially improve imaging and treatments that target somatostatin receptor subtype 2 in neuroendocrine tumors.

Topics: Animals; Cell Line, Tumor; Cell Separation; Depsipeptides; Flow Cytometry; Gene Expression Regulation, Neoplastic; Histone Deacetylase Inhibitors; Humans; Male; Mice; Molecular Imaging; Neuroendocrine Tumors; Organometallic Compounds; Pancreas; Pancreatic Neoplasms; Positron Emission Tomography Computed Tomography; Receptors, Somatostatin; Tissue Array Analysis; Transcription, Genetic; Xenograft Model Antitumor Assays

Somatostatin analog functional imaging with gallium-68 (Ga-68) dotatate positron emission tomography/computed tomography (PET/CT) has demonstrated superiority in lesion detection in patients with neuroendocrine tumors (NETs). The clinical impact of this imaging modality on US surgical and medical oncology practices has not been established.. Consecutive patients with NET at our institution who received an initial Ga-68 dotatate PET/CT between July 2017 and September 2018 were included. Ga-68 dotatate PET/CT was compared with prior imaging.. Among 101 eligible patients, 51 of 50 were female/male, site of origin was gastroenteropancreatic (75%), unknown primary (13%), lung (8%), thymus (2%), and other (2%). All NETs were histologically well/moderately differentiated. Ga-68 dotatate imaging findings altered management in 36 (35.6%) patients: documentation of progression led to the initiation of systemic therapy in 14 patients, obviated the need for biopsy in four patients, and altered surgical plans in 7 of 14 (50%) patients referred for surgery. In 11 patients, decisions regarding peptide receptor radionucleotide therapy and somatostatin analogs were altered.. In this series, Ga-68 dotatate PET/CT altered diagnosis and management in one-third of patients and changed operative plans in half of the patients who were referred for surgical evaluation. These results support the routine use of this imaging in the care of patients with early-stage and advanced NETs.

Topics: Female; Gallium Radioisotopes; Humans; Intestinal Neoplasms; Lung Neoplasms; Magnetic Resonance Imaging; Male; Middle Aged; Neoplasms, Unknown Primary; Neuroendocrine Tumors; Organometallic Compounds; Pancreatic Neoplasms; Positron Emission Tomography Computed Tomography; Radiopharmaceuticals; Retrospective Studies; Stomach Neoplasms; Thymus Neoplasms

Ectopic adrenocorticotropic hormone Cushing syndrome is a relatively rare condition. We present the case of a 39-year-old man with ectopic adrenocorticotropic hormone Cushing syndrome due to a cardiac neuroendocrine tumor (NET), which was localized with the help of Ga-DOTATATE. F-FDG PET/CT revealed a hypermetabolic lesion in the heart, while the distinction between physiological and pathological FDG uptake is difficult. Ga-DOTATATE PET/CT revealed focal uptake corresponding to the cardiac focus found on FDG PET/CT, providing evidence of cardiac NET. This case illustrates that Ga-DOTATATE could play a role in the evaluation of cardiac NET as it lacks significant physiological myocardial uptake.

Topics: Adult; Heart Neoplasms; Humans; Male; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Radiopharmaceuticals

To assess the usefulness of a single-phase contrast-enhanced CT to differentiate subtypes of neuroendocrine tumour (NET) liver metastases and to evaluate the correlation between CT features and Ga-68 DOTATATE positron emission tomography/CT (PET/CT) findings.. Between December 2017 and April 2019 patients with liver metastases of neuroendocrine tumours who underwent CT and Ga-68 DOTATATE PET/CT were enrolled in the study. All patients involved in the study had undergone a standardised single-phase contrast-enhanced CT. Whole body PET/CT images were obtained with a combined PET/CT scanner. All CT images were retrospectively analysed by two radiologists. Enhancement patterns of lesions were assessed. For quantitative examination; CT attenuation values of metastatic lesions, liver parenchyma and aorta were measured using a freehand ROI and tumour-to-liver ratio [T-L = (Tumour-Liver) / Liver] and tumour-to-aorta ratio [T-A = (Tumour-Aorta) / Aorta] were calculated. The lesion with the highest Ga-68 DOTATATE uptake in the liver was used for calculations. The metabolic tumour volume (MTV), maximum standardised uptake value (SUV. A total of 137 NET liver metastases divided into in three groups: 49 (35.7%) pancreatic, 60 (44.5%) gastroenteric and 26 (18.9%) lung NET liver metastases were analysed. Gastroenteric NET metastases often showed heterogeneous enhancement which was significantly higher than in the pancreas and lung NET liver metastases (. We noticed statistically significant differences in both qualitative and quantitative CT features between histologic subgroups of neuroendocrine tumour liver metastases at a single phase contrast-enhanced CT.. Our study will be the first in the literature which extensively focus on assessing the CT features of liver metastases of NETs at a single phase CT and Ga-68DOTATATE PET/CT. As the different histological subtypes of NET liver metastases exhibit different clinical outcomes, these features might help to identify the primary tumour to provide optimal treatment.

Topics: Female; Gastrointestinal Neoplasms; Humans; Liver Neoplasms; Lung Neoplasms; Male; Middle Aged; Neuroendocrine Tumors; Observer Variation; Organometallic Compounds; Pancreatic Neoplasms; Positron Emission Tomography Computed Tomography; Radiopharmaceuticals; Retrospective Studies; Whole Body Imaging

Pancreatic neuroendocrine tumors (PNETs) occur in more than 80% of patients with multiple endocrine neoplasia type 1 (MEN1) syndrome, with predominance of small (<1cm) non-functioning tumors, followed by gastrinomas and insulinomas. Due to their small size, the diagnostic performance of conventional MRI and CT imaging is highly variable, with a real risk of false-negatives. Functional imaging on 111In-DTPA-Octreotide SPECT somatostatin receptor scintigraphy (Octreoscan®) is the modality of choice, but shows only 80% sensitivity. Alternatively, 18F-fluorodihydroxyphenylalanine (FDOPA) and, more recently, 68Ga-Dotatate PET/CT imaging are valuable options in case of negative Octreoscan®.. A 55 old-year woman diagnosed with MEN1 syndrome, presented with multiple asymptomatic but progressive PNETs revealed on ultrasound endoscopy. Octreoscan® was negative, as was 18F-FDOPA PET/CT, whereas 68Ga-Dotatate PET/CT detected all PNETs found on endoscopy.. We here report the first case of a MEN1 patient who successfully underwent a 68Ga-Dotatate PET/CT for detection and follow-up of PNETs, while both Octreoscan® and 18F-FDOPA PET/CT were negative.

Topics: Dihydroxyphenylalanine; Female; Humans; Middle Aged; Multiple Endocrine Neoplasia Type 1; Neuroendocrine Tumors; Organometallic Compounds; Pancreatic Neoplasms; Positron Emission Tomography Computed Tomography

Neuroendocrine tumor (NET) cardiac metastases can be associated with complications including ventricular outflow obstruction, arrhythmias, heart failure, and cardiac arrest, warranting intervention. Anatomical characterization of these lesions via cardiac magnetic resonance (CMR) is helpful to assess and predict the risk of complications and guide therapy. Images of 2 patients with small bowel NET related cardiac metastases are described on Ga-DOTATATE PET/CT and CMR. The lesions were significantly smaller and more obscure on CMR compared with PET/CT. On CMR, T2-weighted dark blood images and late gadolinium enhancement images offered the most conspicuous detection of the NET myocardial metastases in these cases.

Topics: Aged, 80 and over; Female; Heart Neoplasms; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Radiopharmaceuticals

In the diagnostics of neuroendocrine tumors (NETs), scintigraphy and Single Photon Emission Computed Tomography/Computed Tomography (SPECT/CT) with Indium-Octreotide occupy a prominent place.The introduction in clinical practice of Gallium-labelled somatostatin analogues (DOTA-TOC, DOTA-TATE, DOTA-NOC) for Positron Emission Tomography/Computed Tomography (PET/CT), significantly improved NETs diagnostics due to greater sensitivity and improved lesion detection in addition to better patient convenience and decreased radiation dose.. We report a case of a patient who was diagnosed with a neuroendocrine tumor of the ileocecal valve.. Diagnosis was made by ultrasonography, CT, and colonoscopy. Hystology after surgery was G2 NET of ileo-cecal valve. Restaging was carried out by In-Octreotide SPECT/CT and, 1 month later, by Ga-DOTATOC PET/CT. F-FDG PET/C was also carried out.. Ga-DOTATOC PET/CT showed larger disease that modified disease management from surgery to medical treatment.. After an initial improvement in the patient clinical condition, the tumor caused a worsening with the appearance of ascites.. Ga-DOTA-conjugate PET/CT is appropriate in low and intermediate NET (Ki67 index respectively ≤3% and 3%-20%) characterized by better survival and better response after Peptide Receptor Radionuclide Therapy.F-FDG is mostly useful in high grade (G3) of disease, so that Ga-DOTA-conjugate SUV and F-FDG SUV have an opposite trend in relation to the tumor grade. Ga-DOTATOC PET/CT changes, as in our case, therapeutic management in about 40% of cases.

Topics: Aged; Humans; Ileocecal Valve; Male; Neuroendocrine Tumors; Octreotide; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Single Photon Emission Computed Tomography Computed Tomography

A 75-year-old man presented with bleeding ileostomy stoma 20 years after total colectomy and end ileostomy for chronic ulcerative colitis. On physical examination, the stoma was mass-like and firm with friable mucosa. Wedge biopsy of the ileostomy stoma revealed well-differentiated neuroendocrine tumor (intermediate grade). Ga-DOTATATE PET/CT showed mass-like focal radiotracer uptake at the ileostomy site without radiotracer-avid lymphadenopathy or distant metastatic disease. No additional sites of neoplasm in the gastrointestinal tract were further identified by endoscopy. The diagnosis of isolated primary neuroendocrine tumor of the ileostomy stoma was confirmed, an extremely rare entity.

Topics: Aged; Biopsy; Humans; Ileostomy; Male; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography

In our study, tumor heterogeneity was evaluated using the parameters skewness and kurtosis on pretreatment Ga-68 DOTA-TATE PET/CT to assess therapy responses of lesions in patients with gastroenteropancreatic neuroendocrine tumors (GEP NETs) treated with peptide receptor radionuclide therapy (PRRT).. We retrospectively studied the texture analysis with relatively simple first-order parameters skewness and kurtosis on pretreatment Ga-68 DOTA-TATE PET/CT from 22 patients (eight females, 14 males; with a mean age: 54 ± 11 years) with GEP NETs who were treated with 2-6 therapy cycles of Lu-177 DOTA-TATE. A total of 326 lesions of 22 patients were evaluated in terms of treatment response by Ga-68 DOTA-TATE PET/CT examination performed before and after treatment. Receiver-operating characteristic (ROC) curves were generated to assess skewness and kurtosis to discriminate between responder and nonresponder lesions.. A total of 326 lesions of 22 patients were evaluated and 137 lesions responded partially or completely to the treatment, 189 lesions did not respond to treatment, remained stable or progressed. The skewness and kurtosis values of the lesions which did not respond to the PRRT were significantly higher than those with response to PRRT treatment (P < 0.001 and P = 0.004, respectively). However, ROC curves provided a moderate area under the curve value for skewness and a relatively low value for kurtosis (0.619 and 0.518, respectively).. Texture analysis using skewness and kurtosis of the lesions on pretreatment Ga-68 DOTA-TATE PET/CT was able to predict their responsiveness to PRRT.

Topics: Female; Humans; Image Processing, Computer-Assisted; Intestinal Neoplasms; Male; Middle Aged; Neuroendocrine Tumors; Organometallic Compounds; Pancreatic Neoplasms; Positron Emission Tomography Computed Tomography; Receptors, Peptide; Retrospective Studies; ROC Curve; Stomach Neoplasms; Treatment Outcome

Appendiceal neuroendocrine neoplasms (appNEN) generally carry a low recurrence risk. Ga-DOTATATE positron emission tomography (DOTA PET) is increasingly used as it is more sensitive than cross-sectional imaging. We hypothesize that early DOTA PET is unlikely to detect recurrent disease in patients with low-risk resected appNEN because of the delayed pattern of recurrence.. Retrospective study (dual review) of patients undergoing DOTA PET 0 to 18 months after resected appNEN. The primary outcome was the proportion of scans demonstrating residual disease.. Forty-one patients were included (median age, 29 years; 63% female), most with small, low-grade appNEN. No scans (0%) showed residual/distant disease. Eight (20%) of 41 scans showed indeterminate findings requiring follow-up. Five (12%) scans were recommended for follow-up with modalities other than DOTA PET (vertebra, 3; thyroid; bone, 1 each). Three (7%) were recommended for follow-up with DOTA PET (all with indeterminate abdominal uptake). These 3 patients had no recurrent disease on follow-up.. The Ga-DOTATATE PET is of no value when performed in the first 18 months after resected appNEN. Although 20% of scans showed indeterminate findings, more than half did not require repeat DOTA PET. Despite advantages over cross-sectional imaging, DOTA PET is not recommended in staging after completely resected appNEN.

Topics: Adolescent; Adult; Aged; Appendiceal Neoplasms; Female; Follow-Up Studies; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Multimodal Imaging; Neoplasm Recurrence, Local; Neuroendocrine Tumors; Organometallic Compounds; Positron-Emission Tomography; Prognosis; Retrospective Studies; Tomography, X-Ray Computed; Young Adult

The aim was to estimate the physiological standardized uptake values (SUVs) on Ga-DOTATATE PET-computed tomography (CT) in normal organs and metastatic tumor lesions (both standard and delayed), and correlating the uptake values and ratios with Krenning Scores (K-score) in patients with metastatic/advanced neuroendocrine tumors (NETs) undergoing PET-CT studies for their management work-up. A total of 32 patients of metastatic NET with 95 discrete tumor lesions were included in this analysis. These patients underwent standard whole-body PET-CT following injection of 2-3 mCi (74-111 MBq) of Ga-DOTATATE at 1-1.5 h. The normal physiological SUVmean of the liver and spleen and SUVmax and SUVmean of tumor lesions were estimated by an in-built automated procedure. These patients also underwent a delayed scan (2.5-3 h) and the same parameters were obtained for the delayed study. The tumorous lesions were further classified on the basis of K-score, and this was correlated with the mean SUVmax on both early and delayed scans. SUVmean ratios (tumor-to-liver and tumor-to-spleen) were also calculated for both time-points and correlated with individual K-scores. In lesions with K-score 4, the mean SUVmax was 32.5 in early and 30.5 in delayed scan, for lesions with K-score of 3 and 2, the mean SUVmax were 17.3, 20, and 9.3, 9.2, respectively, while in K-score 1 (n = 1), the delayed mean SUVmax was found to be more than early mean SUVmax (3.2 to 2.3). Statistical significance was evaluated by paired t test, and the changes in SUVmax was found to be statistically insignificant (P > 0.05) in all 3 K-scores. The paired t test was also performed between early and delayed tumor/liver and tumor/spleen mean SUVmean ratios, and no significant changes were observed across all K scores. The mean SUVmean values of the liver in the standard 1-h scan and delayed scans were 8.05 (range: 3-15) and 8.17 (range: 3.2-16), while for spleen, the values were 18 (range: 8.4-36.7) and 20 (range: 10-38.6), respectively. Statistically significant changes were observed in delayed spleen SUVmean values compared to the early scan (P < 0.05), while for liver SUVmean, the difference was not significant. Thus, in the present study, the SUVmax and SUVmean (range and mean values) for normal liver and spleen, and malignant NET lesions, and tumor-to-liver and tumor-to-spleen SUVmean ratios of different K-scores were generated. As could be theoretically expected in receptor-based PET-CT, there was no signi

Topics: Adult; Biological Transport; Female; Humans; Male; Middle Aged; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Reference Standards

We investigated the role of Ga-68 DOTATATE PET/CT in comparison to F-18 FDG PET/CT in patients with low and intermediate versus high-grade neuroendocrine tumors (NETs).. We identified 81 patients who underwent Ga-68 DOTATATE PET/CT at our institution between May 2017 and December 2018 and met inclusion criteria of biopsy-proven NET with known Ki-67 index, histologic grade, or differentiation. Patients were divided into two groups. Control group included Ki-67 ≤20%, grade 1 or 2, or well-differentiated tumors. Experimental group included Ki-67 >20%, grade 3, or poorly-differentiated tumors.. Mean age was 57 years, with 36 males and 45 females. Most common primary sites were small bowel, pancreas, and lung. Most common distant metastatic sites were liver and bone. In the control group (n = 67), median Ki-67 was 4% (range 1-30%). 55/67 (82.1%) DOTATATE and 6/11 (54.5%) FDG scans were positive (P = 0.04). Positive scans showed >10 lesions in 25/55 (45.5%) DOTATATE and 1/6 (16.7%) FDG scans (P = 0.18). 40/55 (72.7%) positive DOTATATE and 3/6 (50%) FDG scans showed distant disease (P = 0.25). In the experimental group (n = 14), median Ki-67 was 68% (range 25-95%). All 14 DOTATATE and all nine FDG scans were positive. Positive scans showed >10 lesions in 4/14 (28.6%) DOTATATE and 5/9 (55.6%) FDG scans (P = 0.20). 10/14 (71.4%) positive DOTATATE and 7/9 (77.8%) FDG scans showed distant disease (P = 0.74).. All patients with high grade, poorly-differentiated NETs had positive DOTATATE PET/CTs. In these patients, DOTATATE PET/CT did not significantly differ from FDG PET/CT in identifying >10 lesions or distant disease.

Topics: Female; Fluorodeoxyglucose F18; Humans; Male; Middle Aged; Neoplasm Grading; Neoplasm Metastasis; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography

We report the case of a 46-year-old female patient who presented in the emergency department with intermittent disturbances of perception when fasting.. In the diagnostic fasting test, a hyperinsulinemic hypoglycemia already occurred after 7h. A sonographic examination was inconspicuous, therefore, a Ga 68-HA-DOTATATE positron emission tomography computed tomography (PET-CT) was carried out. The results were indicative of a neuroendocrine neoplasm, which gave rise to the suspicion of an insulinoma.. For surgical treatment the patient was transferred to an external hospital. Following surgery, the patient was free of symptoms.. If multiple symptoms of hypoglycemia are present, an insulinoma as the cause must be considered in the differential diagnostics.

Topics: Fasting; Female; Humans; Hypoglycemia; Insulinoma; Middle Aged; Neuroendocrine Tumors; Organometallic Compounds; Pancreatic Neoplasms; Positron Emission Tomography Computed Tomography; Positron-Emission Tomography; Radionuclide Imaging

We present a case with a pancreatic neuroendocrine tumor and extensive tumor thrombosis in portal venous system. The tumor was first identified on contrast-enhanced CT and later confirmed using Ga-DOTATATE and Ga-NODAGA-LM3 PET/CT. Both tracers demonstrated similar pattern with higher tumor affinity and tumor-to-background ratio using Ga-NODAGA-LM3.

Topics: Acetates; Adult; Aged; Female; Heterocyclic Compounds, 1-Ring; Humans; Male; Middle Aged; Neuroendocrine Tumors; Organometallic Compounds; Portal Vein; Positron Emission Tomography Computed Tomography; Thrombosis

Topics: Carcinoma, Hepatocellular; Humans; Liver Neoplasms; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography

The small bowel neuroendocrine tumor is a rare but ever-increasing tumor, most of the time asymptomatic and found incidentally. An early diagnosis can consistently change the prognosis.

Topics: Asymptomatic Diseases; Biopsy; Endoscopy, Gastrointestinal; Female; Humans; Incidental Findings; Intestinal Neoplasms; Intestine, Small; Middle Aged; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Radiopharmaceuticals

To measure the SUVs in the tail of the pancreas compared with normal liver parenchyma and somatostatin receptor-positive lesions.. Ga-DOTATATE PET/low mAs CT of 35 patients were reviewed.. There was no significant difference (P = 0.59) between the SUVaverage of normal liver and the SUVpeak of normal tail. Five patients had uptake in the tail slightly above that of normal liver that were interpreted equivocally. In one of these patients with Ga-DOTATATE uptake in a peripancreatic lymph node, proven neuroendocrine tumor underwent a distal pancreatectomy and pathologic examination revealed islet cell hyperplasia.. Ga-DOTATATE uptake in the tail of the pancreas above that of normal liver indicates a somatostatin receptor-avid lesion. Uptake in the tail of the pancreas equal to the liver can be normal. Patients with uptake equivalent to the liver should undergo further anatomical imaging before procedural intervention.

Topics: Adult; Aged; Aged, 80 and over; Biological Transport; Female; Humans; Liver; Male; Middle Aged; Neuroendocrine Tumors; Organometallic Compounds; Pancreas; Positron Emission Tomography Computed Tomography; Receptors, Somatostatin

Topics: Gallium; Humans; Neuroendocrine Tumors; Organometallic Compounds; Surgery, Computer-Assisted

Neuroendocrine tumors (NETs) express somatostatin receptors, which can be targeted with radiolabeled peptides. In a variety of solid tumors, radioguided surgery (RGS) has been used to guide surgical resection. Gallium 68 (68Ga) dota peptides have been shown to be more accurate than other radioisotopes for detecting NETs. A pilot study previously demonstrated the feasibility and safety of 68Ga-dotatate RGS for patients with NETs.. To evaluate what intraoperative techniques and thresholds define positive lesions that warrant resection during 68Ga-dotatate RGS.. This prospective cohort study, conducted between October 23, 2013, and February 14, 2018, included 44 patients with NETs who underwent 68Ga-dotatate RGS.. Gallium 68-dotatate RGS.. The in vivo and ex vivo tumor to background ratio (TBR) was assessed for resected lesions and correlated with the histopathologic findings.. Forty-four patients (22 women and 22 men; mean [SD] age, 51.0 [13.7] years) had 133 lesions detected on preoperative imaging scans, with a diagnosis of a pancreatic NET (19 of 44 [43%]), gastrointestinal NET (22 of 44 [50%]), and pheochromocytoma or paraganglioma (3 of 44 [7%]). The TBR was obtained by normalizing to the omentum (106 of 133 [79.7%]) or other solid organs (27 of 133 [20.3%]). The omentum had a significantly lower mean (SD) count than other solid organs for background count activity 3 hours after injection (22.1 [17.0] vs 34.5 [39.0]; P < .001). The lesions containing NETs had a higher TBR than those that did not contain NETs (18.9 vs 4.4; P < .001). On a receiver operating characteristic curve analysis, a TBR of 2.5 had a sensitivity of 90% and a specificity of 25%, and a TBR of 16 had a sensitivity of 54% and a specificity of 81%.. A TBR of 2.5 or greater is a highly sensitive threshold for indicating a lesion to be consistent with a NET on histologic findings and thus warranting surgical resection. The omentum should be used as the background count activity for 68Ga-dotatate RGS for patients with abdominal NETs.

Topics: Female; Gastrointestinal Neoplasms; Humans; Male; Middle Aged; Neuroendocrine Tumors; Organometallic Compounds; Pancreatic Neoplasms; Paraganglioma; Pheochromocytoma; Positron Emission Tomography Computed Tomography; Positron-Emission Tomography; Prospective Studies; Radiopharmaceuticals; Surgery, Computer-Assisted; Treatment Outcome

Prostate large cell neuroendocrine tumor is a rare disease. In this case, metastatic areas showing FDG uptake, somatostatin receptor positivity, and PSMA expression are shown in F-FDG PET/CT, Ga-DOTATATE PET/CT, and Ga-PSMA PET/CT in a 70-year-old man with the diagnosis of prostate large cell neuroendocrine carcinoma.

Topics: Aged; Edetic Acid; Fluorodeoxyglucose F18; Gallium Isotopes; Gallium Radioisotopes; Humans; Male; Neoplasm Metastasis; Neuroendocrine Tumors; Oligopeptides; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Prostatic Neoplasms; Radiopharmaceuticals

A 65-year-old woman with a long history of metastasized, highly differentiated (G1) neuroendocrine tumor of pancreatic origin presented for follow-up Ga-DOTATATE PET/CT after 7 peptide receptor radiotherapies. In the previous scan, she already had discrete intracranial tracer accumulations, which were massively progressive in the recent Ga-DOTATATE PET/CT 8 months later. This case illustrates that cerebral metastases in neuroendocrine tumors may occur many years after initial diagnosis, and their somatostatin receptor expression may rise within a few months to a level that reasonably justifies further peptide receptor radiotherapy.

Topics: Aged; Brain Neoplasms; Humans; Male; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Radiopharmaceuticals

Records of patients who underwent. Performing

Topics: Clinical Decision-Making; Digestive System Neoplasms; Female; Gallium Radioisotopes; Humans; Lung Neoplasms; Male; Middle Aged; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Prospective Studies; Thymus Neoplasms

Schmorl's node (SN) arises from the herniation of the nucleus pulposus of the disc through the cartilaginous endplate into the body of the vertebra. Our report describes a patient with carcinoid tumor who underwent a series of Ga-DOTATATE PET/CT scans for follow-up, demonstrating gradually increasing focal vertebral uptake in absence of CT abnormality, suspicious for a metastasis. Both CT and MRI eventually revealed classical findings of a SN. Also observed in the same vertebra is a degenerative osteophyte showing intense Ga-DOTATATE uptake. This interesting case shows 2 benign spinal lesions, which potentially can simulate bone metastasis in patients with neuroendocrine tumors.

Topics: Aged; Diagnosis, Differential; Humans; Male; Neuroendocrine Tumors; Organometallic Compounds; Osteophyte; Positron Emission Tomography Computed Tomography; Radiopharmaceuticals

Ga-DOTATATE is a radiolabeled somatostatin analog used for the detection and characterization of somatostatin receptor (SSR)-overexpressing tumors, particularly well-differentiated neuroendocrine tumors. We present a case of a 65-year-old man with well-differentiated pancreatic neuroendocrine tumor post-Whipple surgery and a new liver lesion on CT. Ga-DOTATATE PET/CT was performed for SSR characterization and restaging, which demonstrated the lesion to be intensely SSR positive and interpreted as a neuroendocrine metastasis. However, subsequent pathology proved the lesion to be a hepatocellular carcinoma. This case adds hepatocellular carcinoma as a potentially DOTATATE-avid malignancy to be considered in the differential diagnoses of SSR-positive liver lesions.

Topics: Aged; Carcinoma, Hepatocellular; Humans; Liver Neoplasms; Male; Neoplasm Metastasis; Neuroendocrine Tumors; Organometallic Compounds; Pancreatic Neoplasms; Positron Emission Tomography Computed Tomography; Receptors, Somatostatin

Topics: Female; Humans; Magnetic Resonance Imaging; Middle Aged; Neuroendocrine Tumors; Organometallic Compounds; Pancreatectomy; Pancreatic Neoplasms; Positron Emission Tomography Computed Tomography; Radiopharmaceuticals; von Hippel-Lindau Disease

Of the GEP-NEN cases (73 males, 53 females; age 18-77 years) with pathologically proven primary and/or metastatic lesions, 126 were studied. All of the short axes of lesions were larger than 0.5 cm in order to avoid the partial volume effect. Patients fasted for 6 h before the PET/CT scans. The dose of [. In the total sample, the sensitivity of [68Ga]DOTATATE was 69.05 %. The sensitivities were significantly different among G1, G2, and G3 groups (72.22 %, 91.53 %, and 40.82 %, respectively; p < 0.01). The SUVmax of the G3 group was lowest. We also found that the sensitivity and SUVmax were significantly higher (p < 0.05) in patients with pancreatic NENs (Pan-NENs) than in patients with gastrointestinal NENs (Gi-NENs) and unknown primary NENs (Up-NENs). A significant negative correlation between SUVmax and Ki-67 was found (r = - 0.429, p < 0.01). Using SUVmax to differentiate neuroendocrine tumors (NETs) and neuroendocrine cancers (NECs), the area under the ROC curve (AUC) was 0.771 and the cutoff value of SUVmax was 11.25 (sensitivity 79.2 %, specificity 65.3 %). However, Pan-NENs did not show any statistical significance results in correlation and ROC analysis.

Topics: Adolescent; Adult; Aged; Area Under Curve; Cell Proliferation; Female; Humans; Intestinal Neoplasms; Ki-67 Antigen; Male; Middle Aged; Neuroendocrine Tumors; Organometallic Compounds; Pancreatic Neoplasms; Positron Emission Tomography Computed Tomography; Stomach Neoplasms; Young Adult

A 60-year-old woman with recently diagnosed neuroendocrine tumors underwent staging Ga-DOTATATE PET/CT, which revealed focal uptake within the right sacral ala. Histopathology of the right sacral ala confirmed hibernoma. This case illustrates that hibernoma can be a cause of false-positive intraosseous accumulation of Ga-DOTATATE.

Topics: Female; Humans; Lipoma; Middle Aged; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Radiopharmaceuticals

A 54-year-old man with mesenteric carcinoid tumor metastatic to the liver completed staging Ga-DOTATATE PET/CT demonstrating uptake in multiple hepatic lesions consistent with liver metastases with additional asymmetric increased uptake in the right greater than the left breast. Subsequent bilateral diagnostic mammogram revealed benign right greater than left gynecomastia without suspicious underlying mass. With Food and Drug Administration approval of Ga-DOTATATE and the increased use of this analog in neuroendocrine tumor imaging, this case illustrates a relevant example of uptake that can potentially mimic malignancy.

Topics: Diagnosis, Differential; Gynecomastia; Humans; Incidental Findings; Liver Neoplasms; Male; Middle Aged; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography

Neuroendocrine tumors (NET) represent a heterogeneous group of tumors originating from cells of neuroendocrine origin, which express somatostatin receptors (SSTR). This property allowed the successful development of radionuclides for diagnostic and peptide radionuclide radiation therapy (PRRT). This is the paradigm for the theragnostic concept in NET personalized medicine. The only phase III study to date (NETTER-1) clearly demonstrated the ability of

Topics: Clinical Trials, Phase III as Topic; France; Humans; Lutetium; Neuroendocrine Tumors; Octreotide; Organometallic Compounds; Positron-Emission Tomography; Precision Medicine; Radioisotopes; Radiopharmaceuticals; Radiotherapy; Receptors, Somatostatin

Gallium (Ga)-DOTATOC is a somatostatin analog used to detect neuroendocrine tumors (NETs). Ki-67 proliferation index (Ki-67 PI) has been established as a prognostic factor in NETs. We aimed to evaluate whether a correlation exists between Ki-67 PI and somatostatin receptor positron emission tomography (SSTR-PET) uptake.. We retrospectively reviewed 238 DOTATOC PET scans between 2014 and 2016. Patients were excluded if DOTATOC PET was performed more than 365 days from the date of biopsy. Maximum standardized uptake values (SUVmax) of SSTR-PET from biopsied lesions were measured and correlated with Ki-67 PI using the Pearson correlation coefficient.. Among 110 lesions from 90 patients, DOTATOC PET had 92.7% sensitivity and 100% specificity (102 true positives, 8 false negatives) for detection of NETs. Among 63 lesions from 54 patients with Ki-67 PI available, there were 27 grade 1 lesions [median Ki-67 PI, 1.0%; interquartile range (IQR), 1.0-2.0], 30 grade 2 lesions (median, Ki-67 PI 7.5%; IQR, 5-10), and 6 grade 3 lesions (median Ki-67 PI, 30%; IQR, 26-34). There was a correlation between Ki-67 PI and SUVmax (r = -0.3, P = 0.018).. Our analysis demonstrates an inverse correlation between Ki-67 PI and SUVmax in NETs. Somatostatin receptor-PET provides additional information that can help guide management of NETs.

Topics: Adult; Aged; Aged, 80 and over; Female; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Mitotic Index; Neoplasm Grading; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Positron-Emission Tomography; Radiopharmaceuticals; Receptors, Somatostatin; Retrospective Studies

A 66-year-old man with neuroendocrine tumor originating from midgut was referred to Ga-DOTATATE PET/CT imaging for restaging postoperatively. No suspicious uptake regarding residual primary tumoral involvement was seen. But there was diffuse high uptake in prostate gland suggestive of prostatitis or secondary primary tumoral lesion. Concurrent prostate-specific antigen level was 5.02 ng/mL (range, 0-4 ng/mL), C-reactive protein level was 8.25 mg/L (range, <5 mg/L), and white blood cell count was 6.83 × 10/μL (range, 3.9-10.9 × 10/μL). Diagnosis of active chronic prostatitis was achieved by core biopsy, which is identified as potential cause for false-positive diffuse uptake on Ga-DOTATATE PET/CT.

Topics: Aged; Chronic Disease; Humans; Male; Neoplasm Staging; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Prostatitis

A 69-year-old man with recurrent multiple myeloma underwent FDG PET/CT evaluation. A pulmonary nodule without higher-than-background FDG avidity was later biopsied as a low-grade neuroendocrine tumor. On further Ga-DOTATATE PET/CT evaluation of patient's neuroendocrine tumor, the lytic myeloma lesions revealed only mild DOTATATE avidity while the primary pulmonary neuroendocrine tumor showed intense DOTATATE uptake. The distinct imaging characteristics of different primary malignancies correlated with their underlying different pathology.

Topics: Aged; Biopsy; Fluorodeoxyglucose F18; Humans; Lung Neoplasms; Male; Multiple Myeloma; Neoplasm Grading; Neoplasms, Multiple Primary; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography

A 61-year-old man, with a history of prior clear cell renal cell carcinoma in remission, was referred to Ga-DOTATATE PET/CT for the further evaluation of pancreatic tail mass. Ga-DOTATATE PET/CT showed pathologically intense uptake on the pancreatic mass; subsequent biopsy of the pancreatic mass confirmed the diagnosis of clear cell renal cell carcinoma metastasis. Ga-DOTATATE uptake is not specific for neuroendocrine tumors. In the presence of prior malignancy, it should be kept in mind that malignancies apart from neuroendocrine tumors express somatostatin receptors, and they can show Ga-DOTATATE uptake.

Topics: Biological Transport; Carcinoma, Renal Cell; Humans; Kidney Neoplasms; Male; Middle Aged; Neuroendocrine Tumors; Organometallic Compounds; Pancreatic Neoplasms; Positron Emission Tomography Computed Tomography; Receptors, Somatostatin

Ga-DOTATATE PET/CT, a functional imaging modality for assessment of well-differentiated neuroendocrine tumors, targeting the somatostatin receptors, has essentially replaced the conventional gamma camera-based imaging with In-labeled octreotide. Physiologic distribution, normal variations, and common pitfalls with Ga-DOTATATE imaging have been well described in the literature. Here, we describe uptake of Ga-DOTATATE in 2 different patients at cervicothoracic junction within the stellate ganglia.

Topics: Biological Transport; Humans; Middle Aged; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Receptors, Somatostatin; Stellate Ganglion

Ga-DOTATATE PET/CT was performed to determine the cause of endogenous Cushing syndrome in a 10-year-old boy whose MRI studies did not reveal pituitary or adrenal gland abnormality. The PET/CT images demonstrated an intense activity in a small soft tissue nodule in the left upper abdomen where splenules are commonly located. Heat-damaged Tc-labeled red blood cell imaging showed that this soft tissue nodule did not have increased red blood cell activity, which indicated that this lesion was a true somatostatin receptor-rich lesion. The pathology result following surgical resection of the lesion confirmed adrenocorticotropic hormone-producing neuroendocrine tumor.

Topics: Child; Erythrocytes; Hot Temperature; Humans; Image Interpretation, Computer-Assisted; Magnetic Resonance Imaging; Male; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Receptors, Somatostatin

Higher affinity of Ga compounds to somatostatin receptors (SSTRs) and PET better image resolution increased interest in Ga-labelled somatostatin analogs in the management of neuroendocrine tumours (NETs). This study aimed to evaluate the maximum standardized uptake value (SUVmax) variation in sequential somatostatin analogs-PET in NET patients and identify optimal tumour detection and characterization imaging time.. Patients with histological or biochemical NET diagnosis performed two to three PET/computed tomography (CT) scans after intravenous injection of Ga-DOTATATE: Early PET [EarlyPET: <15 minutes postinjection (p.i.)], diagnostic PET (DiagPET: 45-90 minutes p.i.) and delayed PET (DelayPE: 90-240 minutes p.i.). Up to five tumour sites and normal tissues had SUVmax determined. Time-SUVmax curves were created for the target lesions and normal organs. Ratios between tumour and liver SUVmax (SUVTU/Liver) and tumour/blood pool (SUVTU/BP) were also calculated.. Twenty-nine patients were included, 16 female, mean age of 46.5 ± 14.3 years. Average administered activity was 129.5 ± 29.6 MBq. Kidneys SUVmax was higher in EarlyPET compared with DiagPET (P = 0.04) and DelayPET showed higher SUVmax compared with DiagPET for normal liver, pancreas and kidneys (P = 0.02). No differences were noted between EarlyPET, DiagPET and DelayPET in tumour SUVmax (P > 0.05). SUVTU/Liver and SUVTU/BP did not change between EarlyPET and DiagPET, with a slight decrease in DelayPET.. Stability in tumour SUVmax values measured at different intervals independently of tumour location, as also in normal tissues as kidneys and liver suggest that a more flexible imaging protocol may be adopted.

Topics: Adolescent; Adult; Aged; Biological Transport; Female; Humans; Kinetics; Male; Middle Aged; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Young Adult

Ga-DOTATATE imaging is commonly used for the detection of metastatic disease in neuroendocrine tumors. We present a case of a 69-year-old woman postsurgery for lung carcinoid tumor in which sequential follow-up Ga-DOTATATE PET/CT studies identified focal hepatic uptake that was presumed to represent a liver metastasis. However, correlative imaging with MRI revealed a focal fatty sparing of the liver composed of benign hepatic parenchyma at that area accompanied with diffuse liver steatosis in the background of the "pseudolesion." This report demonstrates a potential "false-positive" hepatic finding that can strikingly mimic a metastasis in neuroendocrine tumor imaging.

Topics: Aged; Biological Transport; False Positive Reactions; Fatty Liver; Female; Humans; Liver Neoplasms; Lung Neoplasms; Magnetic Resonance Imaging; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography

Ninety-two patients (44 men and 48 women, mean age of 59.5-year-old) with pathologically confirmed WD-NET (grades 1 or 2) were enrolled in a prospective expanded access protocol. Selected data was analyzed retrospectively for this project. Maximum standardized uptake value (SUV. Univariate analyses revealed significant difference of PFS for WHO tumor grade and ΣSRETV (P < 0.05), while there were no significant differences in age, sex, SUV

Topics: Adult; Aged; Aged, 80 and over; Disease Progression; Disease-Free Survival; Female; Humans; Image Processing, Computer-Assisted; Kaplan-Meier Estimate; Liver Neoplasms; Male; Middle Aged; Multivariate Analysis; Neoplasm Metastasis; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Prognosis; Progression-Free Survival; Proportional Hazards Models; Prospective Studies; Receptors, Somatostatin; Retrospective Studies

Topics: Humans; Interdisciplinary Communication; Ligands; Molecular Imaging; Neuroendocrine Tumors; Organometallic Compounds; Pancreatic Neoplasms; Peptides; Positron Emission Tomography Computed Tomography; Radiopharmaceuticals; Theranostic Nanomedicine

Topics: Aluminum; Chelating Agents; Heterocyclic Compounds, 1-Ring; Humans; Male; Middle Aged; Neoplasm Metastasis; Neuroendocrine Tumors; Octreotide; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Radiopharmaceuticals; Rectal Neoplasms

Respiratory motion during PET/CT acquisition generates artifacts in the form of breath-related blurring, which influences the lesion detectability and diagnostic accuracy. The goal of this study was to verify whether breath-hold [68Ga]DOTA-TOC PET/CT (bhPET) allows detection of additional foci compared to free-breathing PET/CT (fbPET), and to assess the impact of breath-holding on standard uptake values (SUV) and isocontoured volume (Vic40) in patients with neuroendocrine tumors (NET).. Patients with NET (N.=39) were included in this study. BhPET and fbPET characteristics of 96 lesions were compared, and correlated with standard contrast-enhanced (ce) CT and MRI for lesion verification. Quantitative parameters SUV (max and mean) and Vic40 were assessed for both methods and evaluated by linear regression and Spearman's correlation. The impact of lesion size, localization and time interval between investigations was also analyzed.. bhPET identified one additional metastasis not seen at fbPET but visible at ceMRI. Another additional bhPET focus did not have a morphological correlate. At bhPET, the SUVmax and SUVmean proved significantly higher and the Vic40 significantly lower than at fbPET. Lesion size, localization and time intervals did not impact significantly on SUV or Vic40.. Currently, routine use of breath-hold [68Ga]DOTA-TOC PET/CT cannot be recommended as only one additional lesion was identified. Therefore, bhPET has currently no indication in patients with NET. If technical improvements regarding PET/CT scanner sensitivity are available, bhPET should be reevaluated in the future.

Topics: Adult; Aged; Aged, 80 and over; Breath Holding; Female; Humans; Male; Middle Aged; Neoplasm Metastasis; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography

A 76-year-old man known to have a pancreatic neuroendocrine tumor with hepatic and lymph nodes metastasis had a follow-up Ga-DOTATATE PET/CT before Lu-DOTATATE therapy. A new cerebral lesion expressing somatostatin receptors was discovered in the right temporal lobe, suggestive of an ischemic stroke territory. This was later confirmed from the hospital chart where an ischemic stroke was described a month ago.

Topics: Aged; Biological Transport; Brain Ischemia; Humans; Lymphatic Metastasis; Male; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Receptors, Somatostatin; Stroke

Out of 82 PT, 43 PT were not detected by any imaging modality. More PT lesions were detected with PET/CT (n = 39 [47.5%]) than with CE-CT (n = 10 [12.2%], p < 0.001). Also, PET/CT identified significantly more PC lesions than CE-CT (78 and 38%, p = 0.004, respectively).. PET/CT detected more PT and PC lesions than CE-CT. Some PTs and PC lesions were only detected by one of the modalities, and CT performed in conjunction with PET/CT should therefore be performed as a fully diagnostic CE-CT for optimal results. Palpation of the small bowel remains crucial during surgery in these patients because several PTs escaped detection by both PET/CT and CE-CT.

Topics: Adult; Aged; Contrast Media; Female; Gallium Radioisotopes; Humans; Intestinal Neoplasms; Intestine, Small; Male; Middle Aged; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Preoperative Period; Retrospective Studies; Somatostatin; Tomography, X-Ray Computed; Young Adult

Topics: Aged; Female; Humans; Male; Middle Aged; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Reproducibility of Results; Sensitivity and Specificity

Ga-DOTATATE, a positron-emitting somatostatin analog, has been approved by the Food and Drug Administration for imaging neuroendocrine tumors (NETs). The presence of a second primary malignancy is common in NETs; however, synchronous primary malignancy in the thyroid has rarely been reported. The value of Ga-DOTATATE in medullary thyroid cancer is being investigated and is currently recommended for use when treatment with somatostatin analogs is an option. We present a 55-year-old man with abdominal pain associated with well-differentiated NET liver metastases and incidental medullary thyroid carcinoma demonstrated on a Ga-DOTATATE PET/CT.

Topics: Carcinoma, Neuroendocrine; Humans; Incidental Findings; Liver Neoplasms; Male; Middle Aged; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Thyroid Neoplasms

Glucagonoma is an extremely rare, glucagon-secreting neuroendocrine tumor of the pancreas. Only sparse data are available about the characteristics of this tumor in somatostatin receptor imaging and only for the situation of initial diagnosis. We present a series of 3 glucagonoma patients who underwent at least 1 Ga-DOTATATE PET/CT scan. All patients were diagnosed by either histology and/or elevated serum levels of glucagon. The presented cases suggest that somatostatin receptor-based imaging can probably be used for re-evaluation of disease status in patients with glucagonoma in a similar way as it is already established for neuroendocrine tumors of other origin.

Topics: Aged; Female; Follow-Up Studies; Glucagonoma; Humans; Male; Middle Aged; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Receptors, Somatostatin

Sixty six-year-old woman status post ileocecal resection for well-differentiated neuroendocrine tumor in the terminal ileum 7 years ago, who is on octreotide therapy for liver metastases. Ga DOTATATE PET/CT showed soft tissue masses with mildly increased radiotracer uptake in the bilateral subscapular/infrascapular regions. In retrospective image review, these soft tissue masses were first noted 7 years prior and have gradually increased in size over the years. Given the characteristic location and imaging findings, these masses are consistent with benign elastofibroma dorsi instead of metastasis.

Topics: Aged; Diagnosis, Differential; Female; Fibroma; Humans; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Radiopharmaceuticals; Soft Tissue Neoplasms

Topics: Centers for Medicare and Medicaid Services, U.S.; Decision Making; Gallium Radioisotopes; Health Care Costs; Humans; Insurance Claim Review; Insurance, Health; Multimodal Imaging; Neuroendocrine Tumors; Organometallic Compounds; Positron-Emission Tomography; Private Sector; Theranostic Nanomedicine; United States; United States Food and Drug Administration

A case of 25- years-old female with NET deriving from Meckel's diverticulum is described. The patient had one year history of dermatological skin problems. Ultrasound examination of abdomen performed because of arterial hypertension, revealed multiple hepatic lesions, which was confirmed in contrast enhanced CT. The typical contrast enhanced metastatic lesions in CT and elevated levels of chromogranin A suggested NET of unknown origin. SRS with 99mTc-HYNICTOC was perform for primary tumor localization, and revealed liver and paraaortic lymph nodes metastases, but no sign of primary tumor location. As a next step for primary tumor localization 68Ga-DOTATATE PET/CT was done, which revealed focus of increased uptake in small intestine considered to be the primary tumor site. The imaging and clinical history of patient was discussed on ENETS Tumor Board. Due to location of primary tumor in the small intestine with no anatomical changes in CT, laparotomy guided with gamma probe after 68Ga-DOTATATE injection was performed. During surgery procedure, the primary tumor was hardly palpable in the tip of Meckel's diverticulum, confirmed by gamma probe. After surgery, tandem peptide receptor radionuclide therapy (PRRT) was started. Patient received 4 doses of 90Y/177Lu-DOTATATE with total activity of 360 mCi (13.32 GBq). The three months follow up 68Ga-DOTATATE PET/CT had shown stable disease of patient. The presented case showed importance role of multidisciplinary team cooperation in patient management. Use of RGS is essential in cases like presented, when the tumor cannot be localized only by surgical palpation.

Topics: Adult; Disease Management; Female; Humans; Ileal Neoplasms; Meckel Diverticulum; Neuroendocrine Tumors; Octreotide; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Radiopharmaceuticals; Telemedicine

Topics: Humans; Neuroendocrine Tumors; Octreotide; Organometallic Compounds

A 40-year-old man with history of extramedullary plasmacytoma in nasal cavity presented with right submandibular mass for 3 months. F-FDG PET/CT demonstrated mild radioactivity in the right submandibular mass, pancreatic mass, and lymph nodes in the abdomen and left hilum of the lung. To differentiate from pancreatic neuroendocrine tumor, Ga-DOTATATE PET/CT was performed. The above lesions were TATE avid, and additional lesions with intense radioactivity were also detected in the right internal mammary node and intrapericardial node. Finally, biopsy of the right submandibular mass confirmed recurrence of extramedullary plasmacytoma.

Topics: Adult; Diagnosis, Differential; Fluorodeoxyglucose F18; Humans; Intestinal Neoplasms; Lymph Nodes; Male; Neuroendocrine Tumors; Nose Neoplasms; Organometallic Compounds; Pancreatic Neoplasms; Plasmacytoma; Positron Emission Tomography Computed Tomography; Radiopharmaceuticals; Stomach Neoplasms

Focal 68Ga-DOTATATE PET lesions within the myocardium of neuroendocrine tumor (NET) patients are observed in clinical practice. We determined the frequency and characteristics of lesions that are consistent with cardiac metastasis and assessed the lesion detection rate of conventional imaging.. 629 patients who underwent 68Ga-DOTATATE PET-CT at a supraregional comprehensive cancer center on NET were included from a consecutive registry. Inclusion criteria were: (1) focal 68Ga-DOTATATE tracer uptake within the myocardium in more than two sequential PET exams, and (2) contrast-enhanced CT. To determine the diagnostic accuracy of conventional CT imaging, a case-control cohort with a ratio of 1:3 was used. PET and CT were independently analyzed by two blinded readers. Cohen's κ was assessed for interreader agreement. Descriptive statistics were applied for frequencies and characteristics and group comparisons were analyzed using the Fisher's exact test.. The prevalence of myocardial metastases related to the registry was 2.4% (15 of 629 NET patients fulfilling the inclusion criteria), for a total of 21 myocardial 68Ga-DOTATATE foci detected. Myocardial lesions were most frequently located in the left ventricle (43%) and the septum (43%). No patient demonstrated a pericardial effusion. Patients with myocardial metastases did not differ in demographics, tumor grading, disease stage or circulating tumor markers compared to the overall registry (all p > 0.05). Higher Ki67-Indices were observed (p = 0.049) for patients with myocardial metastases. Interreader agreement for PET assessment was excellent (Cohen's κ = 1.0). CT reading showed a sensitivity of 19% (95% confidence interval: 6-43%) at a specificity of 100% (95% confidence interval: 90-100%).. 68Ga-DOTATATE PET enables detection of myocardial metastatic lesions in NET patients. In contrast, standard morphologic CT imaging provides very limited sensitivity.

Topics: Adult; Aged; Female; Heart Neoplasms; Humans; Male; Middle Aged; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography

Patients with pancreatic neuroendocrine tumors (PNET) commonly develop advanced disease and require systemic therapy. However, treatment options remain limited, in part, because experimental models that reliably emulate PNET disease are lacking. We therefore developed a patient-derived xenograft model of PNET (PDX-PNET), which we then used to evaluate two mTOR inhibitor drugs: FDA-approved everolimus and the investigational new drug sapanisertib. PDX-PNETs maintained a PNET morphology and PNET-specific gene expression signature with serial passage. PDX-PNETs also harbored mutations in genes previously associated with PNETs (such as

Topics: Animals; Benzoxazoles; Cell Line, Tumor; Drug Resistance, Neoplasm; Everolimus; Humans; Mice, Nude; Neuroendocrine Tumors; Organometallic Compounds; Pancreatic Neoplasms; Positron Emission Tomography Computed Tomography; Protein Kinase Inhibitors; Pyrazoles; Pyrimidines; TOR Serine-Threonine Kinases; Xenograft Model Antitumor Assays

Ga-DOTATATE PET/CT is currently the most common imaging modality in localizing culprit tumors, which can result in tumor-induced osteomalacia (TIO). Fracture, which is one of the most common consequences of the TIO, can also lead to increased Ga-DOTATATE activity and potentially affect the accuracy of Ga-DOTATATE PET/CT imaging. The aim of this investigation is to evaluate whether the increased Ga-DOTATATE activity at the sites of the fracture will cause interpretation difficulty in the localizing the culprit tumor causing TIO.. The images of Ga-DOTATATE PET/CT scan from a total of 54 patients who had multiple foci of increased Ga-DOTATATE PET/CT on PET/CT were retrospectively analyzed. Not only was the intensity of the activity on PET but also the appearance of the activity on CT taken into consideration when the interpretation of the images occurred. The results from imaging analysis were compared with the clinical chart record. All patients had tentative clinical diagnosis of TIO.. The causative tumors in 53 patients were eventually identified. In 1 patient, the causative tumor was not identified. Among the 53 patients with confirmed TIO, 52 tumors were accurately localized.. Mild activity at the sites of fracture is not a major challenging factor in the interpretation of Ga-DOTATATE PET/CT in the evaluation of TIO when both intensity on PET and morphology on CT were assessed.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Female; Fractures, Bone; Humans; Male; Middle Aged; Neoplasms, Connective Tissue; Neuroendocrine Tumors; Organometallic Compounds; Osteomalacia; Paraneoplastic Syndromes; Positron Emission Tomography Computed Tomography; Radiopharmaceuticals; Reproducibility of Results

Radiopharmaceuticals targeting cell surface expression of somatostatin receptors (SSTRs) are particularly useful in the evaluation of neuroendocrine tumors. Gallium-68 DOTA-Tyr-octreotatate (Ga-DOTATATE) primarily binds to SSTR type 2 receptors. Ga DOTATATE PET/CT is proven to have high impact on the management of neuroendocrine patients compared to traditional anatomical imaging as well as provides additional information over that of conventional nuclear medicine studies (indium-III DTPA-octreotide). It can result in change in management of approximately 75% of patients with neuroendocrine tumors. Ga DOTATATE and F FDG PET/CT imaging are complementary, with the degree of uptake varying depending on the degree of differentiation of the tumor. Well-differentiated tumors maintain their SSTRs and are positive on Ga DOTATATE PET/CT scan, while dedifferentiated tumors are less likely to demonstrate uptake of Ga DOTATATE but will demonstrate uptake with F FDG PET/CT. In addition, Ga DOTATATE PET/CT identifies patients with SSTR expression in their tumors, who have progressed on somatostatin analog therapy, for treatment with Lu DOTATATE.

Topics: Humans; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Practice Guidelines as Topic; Radiology; Radiopharmaceuticals; Societies, Medical

Metastases to the orbit occur rarely in midgut neuroendocrine tumor (NET) patients with only 20 cases reported to date. Patients typically present with bilateral involvement of the recti muscles and experience symptoms such as diplopia, proptosis, and decreased vision. Although orbital MRI remains the gold standard for imaging orbital disease, many orbital lesions are now detected on somatostatin-receptor (SSTR) based imaging such as 68Ga-DOTATATE PET-CT.. Patient 1 is a 72 year-old female with a well-differentiated G3 ileal NET who was incidentally diagnosed with orbital metastases during a hospitalization for pre-septal cellulitis in 2018. Her disease has been controlled with capecitabine rather than local therapy. Patient 2 is a 68 year-old male with a G2 ileal NET who was diagnosed with orbital involvement after developing left peri-orbital swelling in 2017. He was found to have bilateral rectus muscle involvement and was treated with image-guided radiation therapy (IGRT) to both orbits and achieved disease control. Patient 3 is a 63 year-old female with a well-differentiated G3 ileal NET who was incidentally diagnosed with bilateral orbital masses in her recti after undergoing a 68Ga-DOTATATE PET-CT in 2015. She was asymptomatic initially however has now developed diplopia. She will be starting 177Lu-DOTATATE peptide radionuclide receptor therapy (PRRT) shortly. Patient 4 is a 72 year-old male with a grade 2 ileal NET who was incidentally diagnosed with a left lateral rectus metastasis in 2007. This was monitored via surveillance MRI until it began to grow and became symptomatic in 2015. The patient received stereotactic radiation to the site and has been asymptomatic since. Patient 5 is a 61 year-old female with a grade 2 ileal NET who developed progressive diplopia in 2016. Bilateral orbital metastases were noted on orbital MRI and she completed IGRT to the sites shortly thereafter. In the setting of continued growth of the masses she was switched to chemotherapy with capecitabine which has controlled her orbital disease.. NETs can metastasize to the orbits. Orbital disease now often is detected on SSTR-based imaging rather than orbital MRI; when found, it changes treatment approach and surveillance for patients.

Topics: Aged; Female; Humans; Ileal Neoplasms; Intestinal Neoplasms; Magnetic Resonance Imaging; Male; Middle Aged; Neuroendocrine Tumors; Orbital Neoplasms; Organometallic Compounds; Pancreatic Neoplasms; Positron Emission Tomography Computed Tomography; Receptors, Somatostatin; Stomach Neoplasms

Functional imaging tests (FITs) detecting somatostatin receptor expression [i.e., somatostatin receptor scintigraphy, 68Ga-DOTA positron emission tomography/computed tomography (CT)] have a pivotal role in the diagnosis of neuroendocrine tumors (NETs), although their indication during follow-up still needs to be clarified.. Investigate the role of FITs after diagnosis of metastatic enteropancreatic NETs, identifying patients who might benefit from these exams.. Multicenter retrospective analysis of metastatic enteropancreatic NETs.. Analysis of imaging tests performed between January 1995 and December 2015 in Rome, Berlin, Milan, Marburg, or Graz.. One hundred forty-three patients with metastatic pancreatic NETs and small intestine NETs, at least 2-year follow-up, and positive FITs.. Patients had received CT every 6 months (unless clinical conditions and tumor behavior required shorter intervals) and FIT every 12 months.. Clinical usefulness of FITs, defined as changes in patient management (indication to biopsy, medical therapy, surgery, or further imaging tests) due only to FITs.. FITs affected management in 73.4% of patients, mostly when G2 vs G1 [odds ratio (OR), 2.40; 95% confidence interval (CI), 1.09 to 5.27; P = 0.03]. Changes were observed in a 12-month time frame especially with pancreatic NETs vs small intestine NETs (OR, 2.89; 95% CI, 1.09 - 7.67; P = 0.03) or metastases since diagnosis vs developed during follow-up (OR, 4.00; 95% CI, 1.43 to 11.17; P < 0.01).. FITs used in addition to CT in the follow-up of stage IV enteropancreatic NETs improve patient management (especially for G2 tumors). Follow-up program should be tailored according to tumor features.

Topics: Adult; Aged; Female; Follow-Up Studies; Humans; Intestinal Neoplasms; Intestine, Small; Lymph Nodes; Male; Middle Aged; Neoplasm Metastasis; Neuroendocrine Tumors; Organometallic Compounds; Pancreatic Neoplasms; Peritoneal Neoplasms; Positron Emission Tomography Computed Tomography; Radiopharmaceuticals; Retrospective Studies

Ectopic adrenocorticotropic hormone (ACTH) secretion is a less common cause of Cushing syndrome and is seen in 5 to 10% of cases with endogenous hypercortisolemia. We hereby describe our experience of patients with ectopic ACTH syndrome, who have been managed over the past 10 years at a tertiary care center in Southern India.. The inpatient and outpatient records of patients from 2006 to 2015 were retrospectively reviewed. The clinical features, clinical history, biochemical values, imaging features, including radiologic findings and positron emission tomography scans, management, details of follow-up, and outcomes, were documented. We compared the biochemical findings in these patients with 20 consecutive patients with Cushing disease (Cushing syndrome of pituitary origin).. A total of 21 patients were studied. The median age at presentation was 34 years (range, 19 to 55 years). Seven patients had thymic carcinoid, 7 had bronchial carcinoid, 3 had lung malignancies, 2 had medullary carcinoma thyroid, 1 patient had a pancreatic neuroendocrine tumor, and 1 patient had an occult source of ACTH. The most common clinical features at presentation were muscle weakness (95%), hyperpigmentation (90%), facial puffiness (76%), easy bruising (61%), edema (57%), and striae (52%). Extensive acne was seen in a large number of patients (43%). Only 3 patients (14%) had central obesity. The median 8 am cortisol was 55.5 μg/dL (range, 3.8 to 131 μg/dL), median 8 am ACTH was 207 pg/mL (range, 31.1 to 703 pg/mL), and the median 24-hour urinary free cortisol was 2,484 μg (range, 248 to 25,438 μg). Basal cortisol and ACTH, as well as midnight cortisol and ACTH level, were markedly higher in patients with ectopic Cushing syndrome as compared to patients with Cushing disease. Twelve of 21 patients had developed life-threatening infections by follow-up. Nine patients had undergone surgical intervention to address the primary tumor. However, only 1 patient exhibited a complete cure on follow-up.. In our series, ectopic Cushing syndrome was most commonly seen in association with intrathoracic tumors such as bronchial or thymic carcinoid. Hyperpigmentation and proximal myopathy were frequent, while central obesity was uncommon. Early and rapid control of hypercortisolemia was important in order to prevent life-threatening infections and metabolic complications.. ACTH = adrenocorticotropic hormone CT = computed tomography DOTATATE =

Topics: Acne Vulgaris; ACTH Syndrome, Ectopic; Adult; Bronchial Neoplasms; Carcinoid Tumor; Carcinoma, Neuroendocrine; Cushing Syndrome; Edema; Female; Humans; Hydrocortisone; Hyperpigmentation; India; Lung Neoplasms; Male; Middle Aged; Muscle Weakness; Neoplasms; Neuroendocrine Tumors; Obesity, Abdominal; Organometallic Compounds; Pancreatic Neoplasms; Positron-Emission Tomography; Radiopharmaceuticals; Retrospective Studies; Tertiary Care Centers; Thymus Neoplasms; Thyroid Neoplasms; Young Adult

To investigate the accuracy of predicted time-integrated activity coefficients (TIACs) in peptide-receptor radionuclide therapy (PRRT) using simulated dynamic PET data and a physiologically based pharmacokinetic (PBPK) model.. PBPK parameters were estimated using biokinetic data of 15 patients after injection of (152±15)MBq of. For P. Treatment planning of PRRT based on dynamic PET data seems possible for the kidneys, liver and spleen using a PBPK model and patient specific information.

Topics: Computer Simulation; Humans; Kidney; Liver; Models, Theoretical; Neuroendocrine Tumors; Octreotide; Organometallic Compounds; Phantoms, Imaging; Positron-Emission Tomography; Radiopharmaceuticals; Radiotherapy; Radiotherapy Planning, Computer-Assisted; Receptors, Peptide; Spleen

An 81-year-old man with Cushing syndrome was referred for a Ga-DOTATATE PET/CT study to investigate for an ectopic source of adrenocorticotropic hormone. The scan demonstrated mildly increased octreopeptide uptake at a rectal mass and focal uptake at multiple regions throughout the bone marrow of the axial skeleton, consistent with metastases. A subsequent F-FDG PET/CT study was performed for further evaluation and demonstrated markedly increased metabolism at the previously identified rectal mass, in addition to the liver and multiple regions throughout the skeleton. Histopathology from biopsy of the rectal mass confirmed a small cell neuroendocrine carcinoma.

Topics: Adrenocorticotropic Hormone; Aged, 80 and over; Fluorodeoxyglucose F18; Humans; Male; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Rectal Neoplasms

Castrate-resistant prostate cancer (CRPC) often shows histological evidence of neuroendocrine differentiation (NED). To evaluate the extent of NED in patients with CRPC, we used PET/CT with Ga-[DOTA-Tyr]-octreotate (Ga-DOTA-TATE), a somatostatin analog that binds somatostatin receptor 2 with high affinity. This radiotracer is used in imaging of neuroendocrine tumors.. Twelve patients (mean age, 65 [SD, 12] years) with CRPC were studied. Their mean prostate-specific antigen level at scanning was 85.6 (SD, 144.6) ng/mL. PET/CT images were obtained after the injection of 120 to 200 MBq of Ga-DOTA-TATE.. All participants had at least 1 blastic metastasis demonstrating uptake of Ga-DOTA-TATE (mean SUVmax of 5.3 [SD, 2.3]). In 6 patients, moderately high to high uptakes (SUVmax, >5) were seen. Patients with multiple bone metastases had a significantly higher SUVmax compared with patients with few metastases (mean of 5.8 vs 3.8, P = 0.05). In 4 patients, lytic bone lesions or lymph node metastases also showed uptake of the tracer (mean SUVmax of 7.2 [SD, 3.2]). Uptake of the radiotracer was also observed in bones showing normal architecture in CT, suggesting that NED cells appear early during metastases development.. Uptake of Ga-DOTA-TATE is a common finding in metastases of CRPC patients, suggesting that NED is frequent in these patients. In half of the patients, widespread uptake of Ga-DOTA-TATE was observed. This suggests that the possibility of treating selected CRCP patients with anti-neuroendocrine tumor therapies should be explored and that Ga-DOTA-TATE scanning could have a role in predicting the efficacy of these treatments.

Topics: Aged; Aged, 80 and over; Humans; Male; Middle Aged; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Prostatic Neoplasms, Castration-Resistant; Radiopharmaceuticals

Fibroadenoma is the most common benign breast tumor in women of reproductive age, carrying little to no risk of breast cancer development. We report on a case of a woman with history of neuroendocrine tumor who on follow-up imaging tests underwent whole-body PET/CT study using Ga DOTATATE. The scan showed increased focal activity in the right breast, which was biopsied revealing a fibroadenoma. The presented data suggests cell surface overexpression of somatostatin receptors by this benign breast tumor. Moreover, this finding emphasizes the need for cautious interpretation of Ga DOTATATE-avid breast lesions that could mimic malignancy in neuroendocrine tumor patients.

Topics: Adult; Breast Neoplasms; Female; Fibroadenoma; Humans; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Radiopharmaceuticals

To investigate the accuracy of treatment planning in peptide-receptor radionuclide therapy (PRRT) based on simulated PET data (using a PET noise model) and a physiologically based pharmacokinetic (PBPK) model.. The parameters of a PBPK model were fitted to the biokinetic data of 15 patients. True mathematical phantoms of patients (MPPs) were the PBPK model with the fitted parameters. PET measurements after bolus injection of 150 MBq. PET-based treatment planning with kidneys as the dose limiting organ seems possible for all reported noise levels using an adequate PBPK model and previous knowledge about the individual patient.

Topics: Aged; Computer Simulation; Female; Humans; Male; Metabolic Clearance Rate; Middle Aged; Models, Biological; Neuroendocrine Tumors; Organ Specificity; Organometallic Compounds; Positron-Emission Tomography; Radiopharmaceuticals; Radiotherapy Dosage; Radiotherapy Planning, Computer-Assisted; Radiotherapy, Image-Guided; Signal-To-Noise Ratio; Tissue Distribution

Metastatic neureoendocrine tumor to bone is well recognized. Typically, this has an appearance of multiple focal lesions. We present an example of diffuse skeletal involvement on both F-FDG PET/CT and Ga DOTATATE PET/CT with a pattern similar to the superscan appearance described on skeletal scintigraphy.

Topics: Aged; Fluorodeoxyglucose F18; Humans; Male; Neoplasm Metastasis; Neuroendocrine Tumors; Organometallic Compounds; Pancreatic Neoplasms; Positron Emission Tomography Computed Tomography; Radiopharmaceuticals

Primary neuroendocrine tumors of the liver are a diagnostic challenge. We present a rare case of primary hepatic neuroendocrine tumor in which Ga-DOTATATE PET/CT imaging played an important role in the diagnosis and follow-up.

Topics: Adolescent; Humans; Liver Neoplasms; Male; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Radiopharmaceuticals

Fibrous dysplasia of the bone is a developmental benign skeletal disorder characterized by replacement of normal bone and normal bone marrow with abnormal fibro-osseous tissue. We report on a case of a biopsy-proven fibrous dysplasia lesion in the left temporal bone, with intensely increased activity (SUVmax, 56.7) on Ga-DOTATATE PET/CT. The presented data indicate cell surface overexpression of somatostatin receptors by fibrous dysplastic cells and highlight the need of cautious management of Ga-DOTATATE-avid bone lesions, which could mimic malignancy especially in patients with history of neuroendocrine tumors.

Topics: Aged; Diagnosis, Differential; Fibrous Dysplasia of Bone; Humans; Male; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Radiopharmaceuticals

Tail gut cysts are rare congenital lesions developing from postanal primitive gut remnants. They are mostly benign but carry a potential of malignant transformation, such as adenocarcinoma, neuroendocrine tumor, adenosquamous carcinoma, and pseudomyxoma peritonei. We present a 39-year-old woman with a neuroendocrine tumor arising within a tail gut cyst. She underwent complete resection in 2011. After 4 years, she was admitted with breast nodules, left proptosis, and gaze difficulties. Ga-DOTATATE PET/CT demonstrated extensive metastases including pelvic, lymph node, adrenal gland, bone, retro-orbital, cardiac, breast, skin, and subcutaneous metastases.

Topics: Adult; Breast Neoplasms; Female; Heart Neoplasms; Humans; Neuroendocrine Tumors; Orbital Neoplasms; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Radiopharmaceuticals; Skin Neoplasms

Chordoma is a rare slow-growing neoplasm of neuroectodermal origin, which frequently recurs after removal and has the potential to metastasize. We present the case of a 53-year-old man with metastasizing chordoma who underwent F-FDG and Ga-DOTA-TATE PET/CT for restaging of disease and for evaluation of targeted radionuclide therapy potential. On both F-FDG and Ga-DOTA-TATE PET scans, increased tracer accumulation was observed in chordoma metastases. Besides the increased glucose metabolism in chordoma, this case highlights the potential of Ga-DOTA-TATE PET/CT for restaging of chordoma as well the option of targeted radionuclide therapy in this entity.

Topics: Chordoma; Fluorodeoxyglucose F18; Humans; Male; Middle Aged; Neoplasm Metastasis; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Radiopharmaceuticals

PET-CT with somatostatin analogs labeled with Ga is increasingly recognized as the best imaging modality for the evaluation of well-differentiated neuroendocrine tumors (NETs). However, somatostatin receptor (SSR) is not an exclusive marker for NET. A variety of tumors other than NETs express SSR, leading to a significant risk of false-positive PET/CT results. We illustrate false-positive Ga-DOTATATE PET/CT findings due to high uptake by non-Hodgkin lymphoma, metastatic meningioma, breast cancer, thyroid adenoma, and papillary carcinoma. Although Ga-DOTATATE is a noteworthy tracer for oncological application, pathological conditions with overexpression of SSR should be recognized to prevent misinterpretation of PET/CT images.

Topics: Adult; Female; Humans; Male; Middle Aged; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Receptors, Somatostatin

Multiple endocrine neoplasia type 1 (MEN1) is a hereditary syndrome predisposing to many endocrine and neuroendocrine tumors (NET). Conventional imaging (CI) cannot provide satisfactory results for all the different types of MEN1-related tumors. Objective of this prospective observational study was to evaluate the role of (68)Ga-DOTATATE PET/CT in MEN1 compared to CI. Diagnostic performance of (68)Ga-DOTATATE PET/CT for the detection of NET was evaluated as well as the prognostic role of SUVmax. Eighteen patients with genetically confirmed MEN1 were evaluated by (68)Ga-DOTATATE PET/CT, endoscopic ultrasounds, multidetector-row computed tomography, magnetic resonance imaging, and hormone/markers serum measurements. Four MEN1-related tumor sites (pancreas, pituitary, parathyroids, adrenals) were considered. Sensitivity and specificity of (68)Ga-DOTATATE PET/CT for the detection of NET were calculated. There was (68)Ga-DOTATATE PET/CT uptake in 11/11 patients with pancreatic lesions, in 9/12 with pituitary adenoma, in 5/15 with parathyroid enlargements, and in 5/7 with adrenal lesions. (68)Ga-DOTATATE PET/CT showed sensitivity and specificity of 100 and 100 % in pancreas, 75 and 83 % in pituitary, 28 and 100 % in parathyroids, and 62.5 and 100 % in adrenals, respectively. Compared with CI, no significant difference in sensitivity for pancreas, pituitary, and adrenals was found, while CI had a better sensitivity for parathyroids (p = 0.002). On the ROC analysis, progression of pancreatic lesions was significantly associated to SUVmax <12.3 (p < 0.05). (68)Ga-DOTATATE PET/CT is greatly helpful in the work-up of MEN1 providing a panoramic view of MEN1-related lesions. There is also a prognostic role of (68)Ga-PET in patients with MEN1-pancreatic lesions.

Topics: Adenoma; Adolescent; Adult; Female; Humans; Hyperparathyroidism; Male; Middle Aged; Multiple Endocrine Neoplasia Type 1; Neuroendocrine Tumors; Organometallic Compounds; Parathyroid Neoplasms; Pituitary Neoplasms; Positron Emission Tomography Computed Tomography; Predictive Value of Tests; Sensitivity and Specificity; Young Adult

(68)Ga-DOTATATE PET/CT scanning is a widely accepted method for imaging of neuroendocrine tumors. This cross-sectional study was performed to review the first 8 y of patient data from a large (68)Ga-DOTATATE PET/CT database in order to establish the impact of the modality on patient treatment and survival.. Demographic data, clinical outcome, survival, and change in management after (68)Ga-DOTATATE PET/CT were evaluated.. Between May 2005 and August 2013, 1,258 (68)Ga-DOTATATE PET/CT scans were obtained in 728 patients with confirmed or suspected neuroendocrine tumors. In most patients, the primary site was located in the midgut (26.4%). Analysis of NET grading in patients with known histopathologic data revealed that 35.7% had NET grade G1, 12.2% G2, and 8.7% G3. The most common indications for (68)Ga-DOTATATE PET/CT were follow-up (24.4%) and initial tumor staging (23.4%). Of the 1,258 (68)Ga-DOTATATE PET/CT scans completed, 75.7% were positive and 24.3% negative; there were 14 false-positive and 29 false-negative scans. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value were 97%, 95.1%, 96.6%, 98.5%, and 90.4%, respectively. In 40.9% of patients, the treatment plan was changed after the scans, owing mainly to new, unexpected findings. Statistically significant differences in survival were shown between patients with G1, G2, and G3 grade tumors (P < 0.0001) and also between patients with bone metastasis versus patients with soft-tissue metastasis (P < 0.0001).. (68)Ga-DOTATATE PET/CT scanning is safe and influences management in a large proportion of patients. Prognosis was dependent on tumor grade, and the presence of bone metastasis was associated with worse overall survival.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Cross-Sectional Studies; Female; Humans; Male; Middle Aged; Multimodal Imaging; Neoplasm Metastasis; Neuroendocrine Tumors; Organometallic Compounds; Positron-Emission Tomography; Referral and Consultation; Survival Analysis; Tomography, X-Ray Computed; United Kingdom; Young Adult

Schmorl node (SN) is the herniation of the nucleus pulposus through the cartilaginous and bony endplate into the adjacent vertebral body. It is documented that SNs produce areas of moderately increased F-FDG uptake. We present a case of a patient with history of neuroendocrine tumor, who underwent Ga DOTATATE PET/CT for follow-up, showing increased focal vertebral uptake suggestive of bone metastasis. CT revealed typical findings of an SN. The presented case indicates that SNs should be considered when encountering focally increased skeletal uptake in Ga DOTATATE PET/CT studies, which can mimic metastasis in patients with history of neuroendocrine tumors.

Topics: Aged; Diagnosis, Differential; Humans; Intervertebral Disc Degeneration; Intervertebral Disc Displacement; Male; Multimodal Imaging; Neoplasm Metastasis; Neuroendocrine Tumors; Organometallic Compounds; Positron-Emission Tomography; Radiopharmaceuticals; Tomography, X-Ray Computed

Topics: Bone Neoplasms; Carcinoma, Neuroendocrine; Decision Making; Fluorides; Fluorine Radioisotopes; Humans; Neuroendocrine Tumors; Octreotide; Organometallic Compounds; Organophosphorus Compounds; Pain; Positron-Emission Tomography; Precision Medicine; Thyroid Neoplasms; Tomography, X-Ray Computed

Gastro-entero-pancreatic neuroendocrine tumors (GEPNETs) are increasing in incidence, and accurate staging is important for selecting the appropriate treatment. (68)Ga-DOTATATE imaging is a promising approach for detecting GEPNETs and could help in selecting optimal therapeutic strategies. The aim of this study was to prospectively determine the clinical utility of (68)Ga-DOTATATE positron emission tomography (PET)/computed tomography (CT) in detecting unknown primary and metastatic GEPNETs.. One hundred thirty-one patients were enrolled in a prospective study of patients undergoing (68)Ga-DOTATATE PET/CT, (111)In-pentetreotide single-photon emission computed tomography (SPECT)/CT and multiphasic CT scan, and/or magnetic resonance imaging in a blinded fashion with comprehensive biochemical testing. The primary outcome measure was the detection of lesions by each imaging study.. (68)Ga-DOTATATE PET/CT imaging detected 95.1% of lesions (95% CI, 92.4% to 96.8%) with an average maximum standardized uptake value of 65.4 ± 47 (range, 6.9 to 244), anatomic imaging detected 45.3% of lesions (95% CI, 37.9% to 52.9%), and (111)In-pentetreotide SPECT/CT detected 30.9% of lesions (95% CI, 25.0% to 37.5%), with a significant difference between imaging modalities (P < .001). In four of 14 patients (28.6%), (68)Ga-DOTATATE PET/CT found a previously unknown primary tumor, and detected primary GEPNET, lymph node, and distant metastases correctly in 72 of 113 lesions (63.7%) when compared with histopathology, with 22.1% and 38.9% detected by using (111)In-pentetreotide SPECT/CT and anatomic imaging, respectively. On the basis of findings with (68)Ga-DOTATATE PET/CT, 43 of 131 patients (32.8%) had a change in management recommendation. In patients with carcinoid symptoms but negative biochemical testing, (68)Ga-DOTATATE PET/CT detected lesions in 65.2% of patients, 40% of which were detected neither by anatomic imaging nor by (111)In-pentetreotide SPECT/CT.. (68)Ga-DOTATATE PET/CT imaging provides important information for accurate staging of GEPNETs and selection of appropriate treatment interventions even in the absence of biochemical evidence of disease in symptomatic patients.

Topics: Adult; Aged; Aged, 80 and over; Chromogranin A; Female; Humans; Hydroxyindoleacetic Acid; Intestinal Neoplasms; Liver Neoplasms; Lymphatic Metastasis; Magnetic Resonance Imaging; Male; Middle Aged; Multimodal Imaging; Neoplasms, Unknown Primary; Neuroendocrine Tumors; Organometallic Compounds; Pancreatic Neoplasms; Pancreatic Polypeptide; Phosphopyruvate Hydratase; Positron-Emission Tomography; Prospective Studies; Somatostatin; Stomach Neoplasms; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed; Vasoactive Intestinal Peptide; Young Adult

Our purpose was to evaluate the safety and efficacy of (68)Ga-DOTATATE PET/CT compared with (111)In-pentetreotide imaging for diagnosis, staging, and restaging of pulmonary and gastroenteropancreatic neuroendocrine tumors.. (68)Ga-DOTATATE PET/CT and (111)In-pentetreotide scans were obtained for 78 of 97 consecutively enrolled patients with known or suspected pulmonary or gastroenteropancreatic neuroendocrine tumors. Safety and toxicity were measured by comparing vital signs, serum chemistry values, or acquisition-related medical complications before and after (68)Ga-DOTATATE injection. Added value was determined by changes in treatment plan when (68)Ga-DOTATATE PET/CT results were added to all prior imaging, including (111)In-pentetreotide. Interobserver reproducibility of (68)Ga-DOTATATE PET/CT scan interpretation was measured between blinded and nonblinded interpreters.. (68)Ga-DOTATATE PET/CT and (111)In-pentetreotide scans were significantly different in impact on treatment (P < 0.001). (68)Ga-DOTATATE PET/CT combined with CT or liver MRI changed care in 28 of 78 (36%) patients. Interobserver agreement between blinded and nonblinded interpreters was high. No participant had a trial-related event requiring treatment. Mild, transient events were tachycardia in 1, alanine transaminase elevation in 1, and hyperglycemia in 2 participants. No clinically significant arrhythmias occurred. (68)Ga-DOTATATE PET/CT correctly identified 3 patients for peptide-receptor radiotherapy incorrectly classified by (111)In-pentetreotide.. (68)Ga-DOTATATE PET/CT was equivalent or superior to (111)In-pentetreotide imaging in all 78 patients. No adverse events requiring treatment were observed. (68)Ga-DOTATATE PET/CT changed treatment in 36% of participants. Given the lack of significant toxicity, lower radiation exposure, and improved accuracy compared with (111)In-pentetreotide, (68)Ga-DOTATATE imaging should be used instead of (111)In-pentetreotide imaging where available.

Topics: Female; Humans; Indium Radioisotopes; Intestinal Neoplasms; Lung Neoplasms; Male; Middle Aged; Neoplasm Staging; Neuroendocrine Tumors; Observer Variation; Organometallic Compounds; Pancreatic Neoplasms; Positron Emission Tomography Computed Tomography; Safety; Somatostatin; Stomach Neoplasms

We are reporting a case of a 55-year-old woman who was diagnosed as having a non-functioning pancreatic neuroendocrine neoplasm (NF-PNEN), the World Health Organization (WHO) low grade (G1) with liver metastases. In the staging process the positron emission tomography - computed tomography with Fluorine-18-Fluorodeoxyglucose (F-FDG PET-CT) and spiral CT then the gallium-DOTA-octreotate positron emission tomography - computer tomography (⁶⁸Ga-DOTATATE PET-CT) shown difference in burden of disease. In first line therapy, everolimus (Afinitor®, Novartis Pharma GmbH, Germany) at the oral dose of 10 mg once daily and octreotide long-acting release (Sandostatin LAR®) 30 mg i.m. every 4 weeks were administered. Then, due to disease progression - radioisotope therapy with b-emitter Yttrium-90 (⁹⁰Y). Based on this experience and on the review of the literature, we recommend that the discrepancy between the imaging studies could be due to heterogeneity of proliferation rate and somatostatin receptors (SSTR) expression within a primary PNEN and metastases. Therefore in such cases of advanced PNEN WHO G1 in the lack of response to everolimus and octreotide LAR administration isotope therapy without a prior chemotherapy should be considered as a palliative treatment according to ESMO Clinical Practice Guidelines and Polish Network of Neuroendocrine Tumors.

Topics: Female; Fluorodeoxyglucose F18; Humans; Middle Aged; Neoplasm Metastasis; Neuroendocrine Tumors; Organometallic Compounds; Pancreatic Neoplasms; Positron-Emission Tomography; Tomography, X-Ray Computed

Hypergastrinemia is a prominent feature of a segment of gastroenteropancreatic neuroendocrine tumors, the gastrinomas, occurring mostly in the gastrinoma triangle. Hypergastrinemia due to a thoracic neuroendocrine tumor is a very rare occurrence, with a paucity of literature elucidating the same. We report a case of thoracic neuroendocrine tumor in a patient who had initially presented with symptoms of peptic ulcer disease of 3-y duration. On evaluation, the patient's fasting serum gastrin levels were found to be raised. Conventional imaging modalities and endoscopic evaluation did not identify the location of a possible gastrinoma or any other mass in the abdomen. In view of the hypergastrinemia, somatostatin receptor-targeted imaging with (68)Ga-DOTATATE PET/CT was undertaken and showed a somatostatin receptor-expressing paravertebral mass next to the thoracic aorta in the left lung. The mass was excised and was histopathologically suggestive of metastatic neuroendocrine tumor (MIB-1 labeling index, 2%). The present case underscores the importance of (68)Ga-DOTATATE PET/CT in both detecting and characterizing a causative lesion missed on contrast-enhanced CT, especially when the lesion is not easily amenable to biopsy.

Topics: Adult; Gastrins; Humans; Male; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Thoracic Neoplasms

To investigate the relationship between the dynamic parameters (Ki) and static image-derived parameters of 68Ga-DOTATOC-PET, to determine which static parameter best reflects underlying somatostatin-receptor-expression (SSR) levels on neuroendocrine tumours (NETs).. 20 patients with metastasized NETs underwent a dynamic and static 68Ga-DOTATOC-PET before PRRT and at 7 and 40 weeks after the first administration of 90Y-DOTATOC (in total 4 cycles were planned); 175 lesions were defined and analyzed on the dynamic as well as static scans. Quantitative analysis was performed using the software PMOD. One to five target lesions per patient were chosen and delineated manually on the baseline dynamic scan and further, on the corresponding static 68Ga-DOTATOC-PET and the dynamic and static 68Ga-DOTATOC-PET at the other time-points; SUVmax and SUVmean of the lesions was assessed on the other six scans. The input function was retrieved from the abdominal aorta on the images. Further on, Ki was calculated using the Patlak-Plot. At last, 5 reference regions for normalization of SUVtumour were delineated on the static scans resulting in 5 ratios (SUVratio).. SUVmax and SUVmean of the tumoural lesions on the dynamic 68Ga-DOTATOC-PET had a very strong correlation with the corresponding parameters in the static scan (R²: 0.94 and 0.95 respectively). SUVmax, SUVmean and Ki of the lesions showed a good linear correlation; the SUVratios correlated poorly with Ki. A significantly better correlation was noticed between Ki and SUVtumour(max and mean) (p < 0.0001).. As the dynamic parameter Ki correlates best with the absolute SUVtumour, SUVtumour best reflects underlying SSR-levels in NETs.

Topics: Aged; Aged, 80 and over; Biomarkers, Tumor; Female; Humans; Image Enhancement; Image Interpretation, Computer-Assisted; Male; Middle Aged; Molecular Imaging; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Radiopharmaceuticals; Receptors, Somatostatin; Reproducibility of Results; Sensitivity and Specificity

To assess the additional contribution of the combined imaging approach with Ga-DOTA-TATE and fluorine-18 fluorodeoxyglucose (F-FDG) on the basis of volumetric parameters in neuroendocrine tumors (NETs).. Forty-one patients with NET (19 women, 22 men; age range: 30-79 years; mean age: 56.7±12.3 years) underwent Ga DOTA-TATE and F-FDG PET/computed tomography (CT) imaging. Within the drawn regions of interest, in addition to evaluating the maximum and mean standardized uptake values (SUVmax and SUVmean), the metabolic tumor volume (MTV) and total lesion glycolysis (TLG) in F-FDG PET/CT imaging, and the somatostatin receptor density and total lesion somatostatin receptor expression (TLSRE) in Ga somatostatin receptor imaging (SRI) were measured. The patients were graded on the basis of the proliferation index: well (G1; Ki-67 ≤2), moderately (G2; Ki-67=3-20), and poorly (G3; Ki-67>20) differentiated groups.. Of the 41 NET patients, 22, 14, and five were in the G1 (53.7%), G2 (34.1%), and G3 (12.2%) groups, respectively. Liver metastases had significantly higher TLSRE values than the TLG values. Ki-67 levels showed a positive correlation with the primary tumor MTV and TLG values. Cg-A levels had a positive correlation with the volumetric parameters of the whole-body tumor burden (P<0.001).. Ga SRI and F-FDG PET/CT provide complementary information on treatment protocol and response assessment. While assessing the prognosis and tumor aggressiveness, lesions and whole-body tumor burdens can be calculated on the basis of volumetric parameters by F-FDG PET/CT using MTV and TLG, and by Ga SRI using somatostatin receptor density and TLSRE.

Topics: Adult; Aged; Drug Combinations; Female; Fluorodeoxyglucose F18; Humans; Image Enhancement; Male; Middle Aged; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity; Tumor Burden

Topics: Adult; Aged; Female; Humans; Male; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Radiopharmaceuticals; Receptors, Somatostatin; Reproducibility of Results; Sensitivity and Specificity; Treatment Outcome

Neuroendocrine tumours of the pancreas (pNET) are observed in 8 - 17 % of patients with von Hippel-Lindau disease (vHLD), and 11 - 20 % of these patients develop metastatic disease. MRI and CT have a very high resolution; however, their sensitivity and specificity for the detection of pNET amongst cystic lesions in the pancreas of vHLD patients are generally considered insufficient. In contrast, (68)Ga-DOTATOC PET/CT demonstrates a high sensitivity for the diagnosis and staging of neuroendocrine tumours. In this study we investigated the potential role of (68)Ga-DOTATOC PET/CT in screening of patients with vHLD.. (68)Ga-DOTATOC PET/three-phase contrast-enhanced CT was performed according to guidelines in all consecutive vHLD patients between January 2012 and November 2015. All patients underwent additional MRI imaging of the abdomen, spine, and head. Chromogranin A (CgA) was determined at the time of the PET/CT examination. A lesion seen on (68)Ga-DOTATOC PET in the pancreas was defined as positive if the uptake was visually higher than in the surrounding tissues. Lesions were quantified using maximum SUV.. Overall, 20 patients (8 men, 12 women; mean age 44.7 ± 11.1 years) were prospectively examined. Genetically, 12 patients had type 1 vHLD and 8 had type 2 vHLD. (68)Ga-DOTATOC PET/CT detected more pNET than morphological imaging (CT or MRI): 11 patients (55 %; 8 type 1, 3 type 2) vs. 9 patients (45 %; 6 type 1, 3 type 2). The concentration of CgA was mildly elevated in 2 of 11 patients with pNET. The mean SUVmax of the pancreatic lesions was 18.9 ± 21.9 (range 5.0 - 65.6). Four patients (36.4 %) had multiple pNETs. The mean size of the lesions on CT and/or MRI was 10.4 ± 8.3 mm (range 4 - 38 mm), and 41.1 % were larger than 10 mm. In addition, somatostatin receptor-positive cerebellar and spinal haemangioblastomas were detected in three patients (SUVmax 2.1 - 10.1). One patient presented with a solitary somatostatin receptor-positive lymph node metastasis. pNETs were observed more frequently in vHLD type 1 than type 2 (66.7 % vs. 37.5 %, p = 0.089). None of the patients showed progressive disease during follow-up.. In this study, (68)Ga-DOTATOC PET detected pNETs in a higher proportion of patients with vHLD than found in previous studies with (111)In-octreoscan, the imaging method recommended by the NCCN. We therefore suggest (68)Ga-DOTATOC PET/CT as the more sensible screening tool.

Topics: Adult; Diagnosis, Differential; Feasibility Studies; Female; Humans; Male; Mass Screening; Middle Aged; Neuroendocrine Tumors; Organometallic Compounds; Pancreatic Neoplasms; Positron Emission Tomography Computed Tomography; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity; von Hippel-Lindau Disease

Radiolabelled somatostatin analogues detect neuroendocrine tumours (NETs), but may reveal other tumour types. We examined the prevalence of possible meningioma in patients with known or suspected NETs imaged with Ga-DOTATATE PET-computed tomography (CT) on the basis of central nervous system uptake and compared with findings on magnetic resonance and contrast-enhanced CT imaging.. Retrospective imaging reports from 313 patients who had undergone Ga-DOTATATE PET imaging for primary or repeat NET staging were searched to identify suspected meningiomas on PET. Images were then compared with findings on subsequent complementary MRI or contrast-enhanced CT scanning (performed within mean±112 days of PET-CT) if available.. Of 313 patients, 22 had regions of uptake suggestive of meningioma. MRI was available for 12 patients and contrast-enhanced CT was available for one patient. Of these, one patient with known von Hippel-Lindau syndrome had probable cerebellar NET metastasis. Six patient scans indicated lesions consistent with PET. Two of these reported initially did not comment on meningioma. No obvious lesion was found in the remaining six patients; however, five showed a possible correlation to venous structures. The mean maximum standardized uptake value±SEM for lesions in all 21 probable meningioma patients was 4.90±0.45.. Ga-DOTATATE is a sensitive marker of probable meningioma and may identify small lesions not reported on subsequent MRI. Lesions clearly observed on PET were identified on review in half of patients where complementary MR or CT imaging was available. Haemangioblastoma and metastatic NETs may have focal peripheral uptake similar to meningioma on Ga-DOTATATE PET and should be considered in the differential.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Brain; Female; Humans; Magnetic Resonance Imaging; Male; Meningeal Neoplasms; Meningioma; Middle Aged; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Radiopharmaceuticals; Retrospective Studies; Young Adult

We present the FDG and Ga DOTATATE PET/CT findings of a 68-year-old woman with pulmonary metastases 28 years after her initial diagnosis of central nervous system hemangiopericytoma. The largest of the pulmonary lesions showed prominent Ga DOTATATE uptake with comparatively minimal FDG avidity. Hemangiopericytoma is a rare mesenchymal tumor that arises from malignant pericytes, cells that form the walls of capillaries and postcapillary venules. This case demonstrates the potential of radiolabeled somatostatin analogs as a therapeutic option in the setting of widespread metastatic disease.

Topics: Aged; Female; Hemangiopericytoma; Humans; Lung Neoplasms; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Radiopharmaceuticals

The aim of this study was to investigate the accuracy of PET-based treatment planning for predicting the time-integrated activity coefficients (TIACs).. The parameters of a physiologically based pharmacokinetic (PBPK) model were fitted to the biokinetic data of 15 patients to derive assumed true parameters and were used to construct true mathematical patient phantoms (MPPs). Biokinetics of 150 MBq (68)Ga-DOTATATE-PET was simulated with different noise levels [fractional standard deviation (FSD) 10%, 1%, 0.1%, and 0.01%], and seven combinations of measurements at 30 min, 1 h, and 4 h p.i. PBPK model parameters were fitted to the simulated noisy PET data using population-based Bayesian parameters to construct predicted MPPs. Therapy simulations were performed as 30 min infusion of (90)Y-DOTATATE of 3.3 GBq in both true and predicted MPPs. Prediction accuracy was then calculated as relative variability vorgan between TIACs from both MPPs.. Large variability values of one time-point protocols [e.g., FSD = 1%, 240 min p.i., vkidneys = (9 ± 6)%, and vtumor = (27 ± 26)%] show inaccurate prediction. Accurate TIAC prediction of the kidneys was obtained for the case of two measurements (1 and 4 h p.i.), e.g., FSD = 1%, vkidneys = (7 ± 3)%, and vtumor = (22 ± 10)%, or three measurements, e.g., FSD = 1%, vkidneys = (7 ± 3)%, and vtumor = (22 ± 9)%.. (68)Ga-DOTATATE-PET measurements could possibly be used to predict the TIACs of (90)Y-DOTATATE when using a PBPK model and population-based Bayesian parameters. The two time-point measurement at 1 and 4 h p.i. with a noise up to FSD = 1% allows an accurate prediction of the TIACs in kidneys.

Topics: Bayes Theorem; Humans; Models, Biological; Neuroendocrine Tumors; Organometallic Compounds; Phantoms, Imaging; Positron-Emission Tomography; Radiotherapy Planning, Computer-Assisted; Signal-To-Noise Ratio; Time Factors; Tissue Distribution

A 72-year-old man was diagnosed with well-differentiated neuroendocrine tumor of unknown primary with liver metastasis. All liver lesions were detectable only on Ga-DOTATATE PET/CT and were negative on F-FDG PET/CT. Intrahepatic Y radioembolization therapy was planned, but the hepatopulmonary shunt fraction was found to be 31.6%. Because the hepatopulmonary shunt fraction greater than 20% is an absolute contraindication to radioembolization, we decided to give him Lu-DOTATATE therapy. He received 4 courses of Lu-DOTATATE and showed regression in posttherapy Ga-DOTATATE PET/CT imaging. The hepatopulmonary shunt fraction was reduced to 8% after Lu-DOTATATE therapy.

Topics: Aged; Fluorodeoxyglucose F18; Humans; Liver Neoplasms; Male; Neuroendocrine Tumors; Octreotide; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Radiopharmaceuticals

A 33-year-old woman with McCune-Albright syndrome was referred for a Ga-DOTATATE PET/CT study for evaluation and staging of a biopsy-proven pancreatic tail neuroendocrine tumor. The scan demonstrated intense focal octreopeptide uptake corresponding to the known neuroendocrine tumor at the pancreatic tail/splenic hilum. There was no evidence of octreopeptide-avid metastases. Diffuse octreopeptide uptake was demonstrated in multiple bones involving the right side of the skeleton. The concurrent CT demonstrated corresponding expansile lucent changes consistent with the known fibrous dysplasia.

Topics: Adult; Bone and Bones; Female; Fibrous Dysplasia, Polyostotic; Humans; Neuroendocrine Tumors; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Radionuclide Imaging; Radiopharmaceuticals

Neuroendocrine tumors (NETs) are rare tumors, but the incidence is increasing with new diagnostics. A 37-year-old man was admitted to our hospital for an incidental 17-mm nodule in the tail of the pancreas. PET/CT shows indeterminate mass in the pancreatic tail with enhanced uptake of 68-Ga-dotatate. NET was suspected and laparoscopic distal pancreatectomy was performed. Pathologic examination revealed an accessory spleen with a heterotopic location. To the best of our knowledge, this is the first intrapancreatic accessory spleen (IPAS) case in which the positive 68-Ga-dotatate uptake reported in the literature. Our case showed that IPAS is one of the reasons of false positive involvement of 68-Ga-dotatate PET/CT. When PET/CT shows an indeterminate mass in the pancreatic tail with enhanced uptake of 68-Ga-dotatate, surgeons should keep IPAS in their mind for differential diagnosis to avoid false treatment.

Topics: Adult; Choristoma; Diagnosis, Differential; Humans; Male; Neuroendocrine Tumors; Organometallic Compounds; Pancreatectomy; Pancreatic Diseases; Pancreatic Neoplasms; Positron Emission Tomography Computed Tomography; Spleen; Ultrasonography

Resection is the only curative treatment in patients suffering from neuroendocrine tumors (NETs) of the ileum or the pancreas. Accurate preoperative imaging is critical for surgical planning, as even findings of small and distant metastases may profoundly influence surgical management.. (68)Ga-DOTATATE PET/CT was performed preoperatively in 44 patients suffering from NET of the ileum (n = 26) or the pancreas (n = 18) before surgery at our University Hospital. Data were analyzed retrospectively by an interdisciplinary team of nuclear medicine and visceral surgery specialists. Intended surgical management was documented before and after availability of PET/CT findings. The team judged whether the imaging findings provided additional information relevant to surgical planning.. Imaging results altered surgical management in 9 of 44 (20 %) patients, more specifically in 3 of 26 (12 %) patients with NET of the ileum and in 6 of 18 (33 %) patients with NET of the pancreas. PET/CT findings led to a more invasive surgical approach in 6 cases (3 each of ileum and pancreas) and to a less invasive strategy in 3 patients with NET of the pancreas. Although PET/CT results did not alter management in 35 of 44 patients, somatostatin receptor imaging still provided additional information for surgery planning in more than 95 % of the cases.. Additional information provided by (68)Ga-DOTATATE PET/CT in the preoperative workup significantly influences surgical management in one-fifth of our NET patients and, notably, one-third of those suffering from NET of the pancreas.

Topics: Adult; Aged; Disease Management; Female; Follow-Up Studies; Gallium Radioisotopes; Humans; Ileal Neoplasms; Lymphatic Metastasis; Male; Middle Aged; Multimodal Imaging; Neoplasm Staging; Neuroendocrine Tumors; Organometallic Compounds; Pancreatic Neoplasms; Positron-Emission Tomography; Prognosis; Retrospective Studies; Tomography, X-Ray Computed

Somatostatin receptor imaging with (68)Ga-DOTATATE PET/CT (DOTATATE) is increasingly used for managing patients with neuroendocrine tumors. The objective of this study was to determine referring physicians' perspectives on the impact of DOTATATE on the management of neuroendocrine tumors.. A set of 2 questionnaires (pre-PET and post-PET) was sent to the referring physicians of 100 consecutive patients with known or suspected neuroendocrine tumors, who were evaluated with DOTATATE. Questionnaires on 88 patients were returned (response rate, 88%). Referring physicians categorized the DOTATATE findings on the basis of the written PET reports as negative, positive, or equivocal for disease. The likelihood for metastatic disease was scored as low, moderate, or high. The intended management before and changes as a consequence of the PET study were indicated.. The indications for PET/CT were initial and subsequent treatment strategy assessments in 14% and 86% of patients, respectively. Referring physicians reported that DOTATATE led to a change in suspicion for metastatic disease in 21 patients (24%; increased and decreased suspicion in 9 [10%] and 12 [14%] patients, respectively). Intended management changes were reported in 53 of 88 (60%) patients. Twenty patients (23%) scheduled to undergo chemotherapy were switched to treatments without chemotherapy, and 6 (7%) were switched from watch-and-wait to other treatment strategies. Conversely, 5 patients (6%) were switched from their initial treatment strategy to watch-and-wait.. This survey of referring physicians demonstrates a substantial impact of DOTATATE on the intended management of patients with neuroendocrine tumors.

Topics: Adult; Aged; Aged, 80 and over; Female; Humans; Image Interpretation, Computer-Assisted; Male; Middle Aged; Multimodal Imaging; Neoplasm Metastasis; Neuroendocrine Tumors; Organometallic Compounds; Physicians; Positron-Emission Tomography; Referral and Consultation; Research Report; Surveys and Questionnaires; Tomography, X-Ray Computed

⁶⁸Ga DOTATATE PET/CT is a well-established method in the diagnostic workup of neuroendocrine tumors. We report the case of a 15-year-old adolescent boy with histologically proven appendiceal carcinoid tumor referred for ⁶⁸Ga DOTATATE PET/CT to identify residual or metastatic disease. PET images showed increased tracer uptake in the body of T4 vertebra. This uptake could be misdiagnosed for bone metastasis, but CT characteristic appearance was in keeping with vertebral hemangioma. Both bone metastasis in carcinoid tumor and bone hemangiomas in adolescents are rare conditions, but the combined metabolic and morphological information on PET/CT can lead to the correct diagnosis.

Topics: Adolescent; Carcinoid Tumor; Hemangioma; Humans; Male; Multimodal Imaging; Neoplasm Metastasis; Neuroendocrine Tumors; Organometallic Compounds; Positron-Emission Tomography; Radiopharmaceuticals; Spinal Neoplasms; Tomography, X-Ray Computed

Radiolabeled peptides for tumor imaging with PET that can be produced with kits are currently in the spotlight of radiopharmacy and nuclear medicine. The diagnosis of neuroendocrine tumors in particular has been a prime example for the usefulness of peptides labeled with a variety of different radionuclides. Among those, (68)Ga and (18)F stand out because of the ease of radionuclide introduction (e.g., (68)Ga isotope) or optimal nuclide properties for PET imaging (slightly favoring the (18)F isotope). The in vivo properties of good manufacturing practice-compliant, newly developed kitlike-producible (18)F-SiFA- and (18)F-SiFAlin- (SiFA = silicon-fluoride acceptor) modified TATE derivatives were compared with the current clinical gold standard (68)Ga-DOTATATE for high-quality imaging of somatostatin receptor-bearing tumors.. SiFA- and SiFAlin-derivatized somatostatin analogs were synthesized and radiolabeled using cartridge-based dried (18)F and purified via a C18 cartridge (radiochemical yield 49.8% ± 5.9% within 20-25 min) without high-performance liquid chromatography purification. Tracer lipophilicity and stability in human serum were tested in vitro. Competitive receptor binding affinity studies were performed using AR42J cells. The most promising tracers were evaluated in vivo in an AR42J xenograft mouse model by ex vivo biodistribution and in vivo PET/CT imaging studies for evaluation of their pharmacokinetic profiles, and the results were compared with those of the current clinical gold standard (68)Ga-DOTATATE.. Synthetically easily accessible (18)F-labeled silicon-fluoride acceptor-modified somatostatin analogs were developed. They exhibited high binding affinities to somatostatin receptor-positive tumor cells (1.88-14.82 nM). The most potent compound demonstrated comparable pharmacokinetics and an even slightly higher absolute tumor accumulation level in ex vivo biodistribution studies as well as higher tumor standardized uptake values in PET/CT imaging than (68)Ga-DOTATATE in vivo. The radioactivity uptake in nontumor tissue was higher than for (68)Ga-DOTATATE.. The introduction of the novel SiFA building block SiFAlin and of hydrophilic auxiliaries enables a favorable in vivo biodistribution profile of the modified TATE peptides, resulting in high tumor-to-background ratios although lower than those observed with (68)Ga-DOTATATE. As further advantage, the SiFA methodology enables a kitlike labeling procedure for (18)F-labeled peptides advantageous for routine clinical application.

Topics: Animals; Binding, Competitive; Diagnostic Imaging; Fluorides; Fluorine Radioisotopes; Gallium Radioisotopes; Mice; Neoplasm Transplantation; Neuroendocrine Tumors; Octreotide; Organometallic Compounds; Peptides; Positron-Emission Tomography; Radiopharmaceuticals; Rats; Receptors, Somatostatin; Silicon; Tissue Distribution; Tomography, X-Ray Computed

Diagnosis of ectopic adrenocorticotropic hormone (ACTH) and corticotropin-releasing hormone (CRH) co-secreting tumors causing Cushing syndrome (CS) is challenging because these tumors are rare and their diagnosis is frequently confused with Cushing disease (CD), caused by the effect of CRH on the pituitary. We report a case of a 21-year-old male patient who was referred to our institution with persistent hypercortisolemia and CS after undergoing unnecessary transsphenoidal surgery (TSS). ⁶⁸Ga-DOTA-TATE PET/CT revealed increased tracer uptake in the thymus, which was histologically proven to be a neuroendocrine tumor (NET) that stained positive for ACTH and CRH. Imaging with ¹⁸F-FDG PET/CT was not diagnostic.

Topics: Adrenocorticotropic Hormone; Corticotropin-Releasing Hormone; Cushing Syndrome; Fluorodeoxyglucose F18; Humans; Male; Multimodal Imaging; Neuroendocrine Tumors; Organometallic Compounds; Positron-Emission Tomography; Radiopharmaceuticals; Thymus Neoplasms; Tomography, X-Ray Computed; Young Adult

Besides well-known physiologic uptake of Ga-DOTATATE in spleen, pituitary gland, pancreatic head, adrenals, kidney, and urinary bladder, sometimes unusual areas of uptake are found. We report a case of a 53-year-old woman who had vague pain in abdomen for which abdominal CT was done showing a contrast-enhancing lesion in the pancreatic tail. It was suspected to be of neuroendocrine origin and Ga-DOTATATE PET/CT showed a corresponding focal uptake. Spleen-preserving pancreatic tail resection was performed. Pathology revealed the diagnosis of an accessory intrapancreatic spleen (AIPS).

Topics: Female; Humans; Middle Aged; Multimodal Imaging; Neuroendocrine Tumors; Organometallic Compounds; Pancreas; Positron-Emission Tomography; Radiopharmaceuticals; Spleen; Tomography, X-Ray Computed

To compare and outline the beneficial skills of combined (68)Ga-DOTATATE positron emission tomography (PET) with concurrent contrast enhanced X-ray computed tomography (ceCT) against stand-alone ceCT in 54 patients with neuroendocrine tumours (NET).. Patients with histologically confirmed NET and available follow-up of at least 6 months (median 12.6 months; range 6.1-23.2) were included. PET/CT and ceCT images were initially analyzed separately by two blinded nuclear medicine physicians and two radiologists, respectively. In a second step all four physicians reviewed all detected lesions together reaching a consensus-grading for PET/ceCT. The results were then compared to the reference standard consisting of clinical follow-up data.. With regard to true positive lesions, PET/ceCT vs. stand alone ceCT detected 139 vs. 48 bone-lesions, 106 vs. 71 lymph node metastases and 26 vs. 26 pulmonary lesions. On a per-patient basis, PET/ceCT achieved a higher sensitivity (100% vs. 47%) and specificity (89% vs. 49%) for bone lesions than ceCT. For lymph nodes the effect was similar (sensitivity 92% vs. 64% and specificity 83% vs. 59%). For the detection of pulmonary lesions the sensitivity was identical (100%) while specificity of PET/ceCT was superior to ceCT-alone (95% vs. 82%).. In summary, the use of (68)Ga-DOTATATE PET/ceCT leads to an increase in sensitivity and specificity in the detection of extra-hepatic NET metastases compared to stand-alone ceCT. Therefore, (68)Ga-DOTATATE PET/ceCT should be the imaging modality of choice in patients with NET.

Topics: Adult; Aged; Aged, 80 and over; Bone Neoplasms; Contrast Media; Female; Follow-Up Studies; Humans; Image Processing, Computer-Assisted; Liver Neoplasms; Lung Neoplasms; Lymphatic Metastasis; Male; Middle Aged; Multimodal Imaging; Neoplasm Grading; Neoplasm Staging; Neuroendocrine Tumors; Organometallic Compounds; Positron-Emission Tomography; Predictive Value of Tests; Reference Standards; Sensitivity and Specificity; Tomography, X-Ray Computed; Whole Body Imaging

The objective of this study was to identify a more rapid assay for (68)Ga(OH)3 impurity in (68)Ga-DOTATATE formulations. Three methods were used to prepare (68)Ga(OH)3 reference material (pharmacopoeial, bench titration and automated radiosynthesis), and four quality control methods for its assessment (thin layer chromatography, membrane filtration, HPLC and solid phase extraction). The optimal method of preparing (68)Ga(OH)3 was by titrating (68)Ga(3+) with buffered sodium hydroxide solutions to pH 5.6 ± 0.2. The precipitate was quantitatively isolated by membrane filtration (0.02 µm)/hydrochloric acid (HCl; pH 5.6) solvent, and also it remained 100% at the origin on instant thin layer chromatography with silica gel paper/HCl (pH 5.6) solvent. For (68)Ga-DOTATATE samples, the thin layer chromatography technique was used with a single paper strip developed separately on two occasions, once in HCl (pH 5.6) and next in methanol solvent. This so-called double-developed (DD) method separated (68)Ga(OH)3 impurity located at the origin, from (68)Ga-DOTATATE plus (68)Ga(3+) at ~Rf 0.4, and it was superior to the other methods. It assayed for the impurity similarly to the pharmacopoeial method. The advantages of the DD method were that it required inexpensive test materials and it reproducibly determined % (68)Ga(OH)3 in (68)Ga-DOTATATE in 12 min, 13 min earlier than the pharmacopoeial method. This time efficiency resulted in a surplus of 12% (68)Ga-DOTATATE counts in the product vial, and this provided a contingency of radioactivity or time for the injection/imaging processes in the Nuclear Medicine Department.

Topics: Chromatography, Liquid; Drug Contamination; Gallium Radioisotopes; Humans; Hydroxides; Neuroendocrine Tumors; Organometallic Compounds; Radionuclide Imaging; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity

Surgery is the only definitive therapy for gastro-entero-pancreatic neuroendocrine tumors (GEPNETs), and achieving complete tumor resection is an important prognostic factor. Radiopharmaceuticals such as (68)Ga-DOTA peptides have been developed that offer superior accuracy for localization of GEPNETs. The study aim was to determine the feasibility of radio-guided surgery (RGS) using (68)Ga-DOTATATE in patients with primary and recurrent GEPNETs.. Fourteen patients with GEPNETs were enrolled onto a prospective study to determine the feasibility of RGS with (68)Ga-DOTATATE. Findings from preoperative imaging, intraoperative exploration, RGS, and pathology were analyzed.. The median decay corrected target count rate was 172.6 (range 28.15-2341) for tumors, with a tumor-to-background ratio (TBR) of 4.46 (range 1.6-43.56). The median lesion size was 1.55 (range 0.5-15) cm. There was no significant correlation between preoperative imaging maximum standardized uptake value (SUVmax) of the lesions and TBR (Spearman r = - 0.01, p = 0.9), TBR and tumor size (Spearman r = 0.29, p = 0.14), and SUVmax and tumor size (Spearman r = 0.22, p = 0.28). The probe showed correct identification for gastric and small intestine neuroendocrine tumor (NET), including lymph node metastasis in 17 (81.0 %) of 21 cases, with a median TBR of 3.5 (1.6-40.2). For pancreatic NETs and lymph node metastasis, 16 (66.7 %) of 24 were correctly identified by RGS.. Our study shows that RGS with (68)Ga-DOTATATE is feasible and correctly confirms bowel NETs and metastatic mesenteric lymph nodes. Further studies are needed to determine the benefit of RGS with (68)Ga-DOTATATE.

Topics: Adult; Aged; Biomarkers, Tumor; Feasibility Studies; Female; Follow-Up Studies; Humans; Image Processing, Computer-Assisted; Immunoenzyme Techniques; Intestinal Neoplasms; Male; Middle Aged; Multimodal Imaging; Neoplasm Grading; Neoplasm Staging; Neuroendocrine Tumors; Organometallic Compounds; Pancreatic Neoplasms; Positron-Emission Tomography; Prognosis; Prospective Studies; Radiopharmaceuticals; Radiotherapy, Image-Guided; Stomach Neoplasms; Tissue Distribution; Tomography, X-Ray Computed

The objective of this study was to evaluate the correlation between dynamic gadoxetic acid-enhanced magnetic resonance imaging parameters and specific uptake values (SUVs) derived from ¹⁸fluorodeoxyglucose (¹⁸F-FDG) and ⁶⁸Ga-DOTA-Tyr(3)-octreotate (⁶⁸Ga-DOTATATE) positron emission tomography/computed tomography (PET/CT) in patients with liver metastases of neuroendocrine neoplasms.. A total of 42 patients with hepatic metastases of neuroendocrine neoplasms were prospectively enrolled and underwent both dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and PET/CT, using either ¹⁸F-FDG or ⁶⁸Ga-DOTATATE as tracer. The DCE-MRI was performed at 3 T with gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid acquiring 48 slices every 2.2 seconds for 5 minutes. Three regions of interest (ROIs) representing the liver background and up to 3 ROIs representing metastatic liver tissue were coregistered in the PET/CT and in the DCE-MRI data sets. For each patient, a dedicated dual-inlet, 2-compartment uptake model was fitted to the enhancement curves of DCE-MRI ROIs and perfusion parameters were calculated. Lesion-to-background ratios of SUVs were correlated with corresponding lesion-to-background ratios of the perfusion parameters arterial plasma flow, venous plasma flow, total plasma flow, extracellular mean transit time, extracellular volume, arterial flow fraction, intracellular uptake rate, and hepatic uptake fraction using the Spearman coefficient.. Whereas the lesion-to-background ratios of arterial plasma flow and arterial flow fraction of liver metastases correlated negatively with the lesion-to-background ratios of SUV(mean) derived from ⁶⁸Ga-DOTATATE PET/CT (r = -0.54, P < 0.001; r = -0.39, P < 0.001, respectively), they correlated positively with the lesion-to-background ratios of SUV(mean) derived from ¹⁸F-FDG-PET/CT (r = 0.51, P < 0.05; r = 0.68, P < 0.01, respectively). The lesion-to-background ratios of the DCE-MRI parameters extracellular mean transit time and extracellular volume correlated very weakly with the lesion-to-background ratios of SUV(mean) from ⁶⁸Ga-DOTATATE PET/CT, whereas venous plasma flow, total plasma flow, hepatic uptake fraction, and intracellular uptake rate showed no correlation between DCE-MRI and PET/CT.. Both ⁶⁸Ga-DOTATATE and ¹⁸fluorodeoxyglucose PET/CT partially correlate with MRI perfusion parameters from the dual-inlet, 2-compartment uptake model. The results indicate that the paired imaging methods deliver complementary functional information.

Topics: Contrast Media; Coordination Complexes; Female; Fluorodeoxyglucose F18; Humans; Image Interpretation, Computer-Assisted; Liver Neoplasms; Magnetic Resonance Imaging; Male; Middle Aged; Multimodal Imaging; Neuroendocrine Tumors; Octreotide; Organometallic Compounds; Positron-Emission Tomography; Reproducibility of Results; Sensitivity and Specificity; Tomography, X-Ray Computed

PET with (68)Ga-DOTATOC allows for imaging and quantitative assessment of somatostatin receptor expression in neuroendocrine tumors (NET). The aim of this retrospective study was to analyze whether pre-therapeutic (68)Ga-DOTATOC PET/CT is able to predict response to Peptide Receptor Radionuclide Therapy (PRRT).. Forty patients with advanced stage NET were treated with a fixed dose of (90)Y-DOTATOC (5550 or 3700MBq). Prior to PRRT, each patient received (68)Ga-DOTATOC PET/CT. Treatment results were evaluated after 3months by CT, tumor marker levels and clinical course and correlated with (68)Ga-DOTATOC uptake (SUVmax) and the assumed uptake of (90)Y-DOTATOC in tumor manifestations (MBq/g). ROC analysis and pairwise comparison of area under the curve (AUC) were performed with pre-treatment uptake of (68)Ga-DOTATOC, assumed uptake of (90)Y-DOTATOC and treatment activity alone and in relation to body weight as continuous variables, and response/no response as classification variable.. According to conventional criteria (tumor shrinkage, decrease of tumor markers, improved or stable clinical condition), 20 patients were classified as responders, 16 as non-responders and in four patients findings were equivocal. Using a SUV more than 17.9 as cut-off for favorable outcome, PET was able to predict treatment response of all responders and 15 out of 16 non-responders. All four patients with equivocal findings showed SUV less than or equal to 17.9 and soon experienced tumor progression. The assumed uptake of (90)Y-DOTATOC in tumor manifestations using a cut-off more than 1.26MBq/g as predictor of response was able to correctly classify 19 out of 20 responders, and 14 out of 16 non-responders. In all patients with equivocal findings, the assumed uptake of (90)Y-DOTATOC was below 1.26MBq/g.. Pre-therapeutic (68)Ga-DOTATOC tumor uptake as well as assumed uptake of (90)Y-DOTATOC are strongly associated with the results of subsequent PRRT. The defined cut-off values should be confirmed by prospective studies and may then provide the rationale for individual dosing and selecting patients with high likelihood of favorable treatment outcome.

Topics: Adult; Aged; Cooperative Behavior; Endovascular Procedures; Female; Follow-Up Studies; Humans; Interdisciplinary Communication; Male; Middle Aged; Neoplasm Staging; Neuroendocrine Tumors; Organometallic Compounds; Positron-Emission Tomography; Predictive Value of Tests; Receptors, Somatostatin; Retrospective Studies; Tomography, X-Ray Computed; Treatment Outcome

To evaluate diagnostic performance of gallium 68-tetraazacyclododecane tetraacetic acid-octreotate ((68)Ga-DOTATATE) in detection of recurrent neuroendocrine tumors (NETs).. Approval was waived by the local ethics committee for this retrospective study. Between 2007 and 2011, 63 patients (mean age, 58 years) were examined with (68)Ga-DOTATATE positron emission tomography (PET)/computed tomography (CT) after primary NET curative resection. Reasons for PET/CT were regular follow-up examinations (n = 30), increased plasma levels of tumor markers (n = 27), or clinical suspicion of recurrence (n = 6). Final diagnosis was determined with histopathologic verification (n = 25) or clinical follow-up (n = 38). PET/CT scans were evaluated in consensus by two readers without blinding to clinical information and independently by two readers with blinding. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated.. Final diagnosis of NET recurrence was determined in 29 patients. In three other patients, tumors of nonneuroendocrine origin were diagnosed. (68)Ga-DOTATATE PET/CT helped identify NET recurrence in 26 of 29 patients (sensitivity, 90%) and exclude presence of recurrent NET in 28 of 34 patients (specificity, 82% ). PET/CT provided false-positive and false-negative results in six and three patients (PPV, 81% [26 of 32]; NPV, 90% [28 of 31]; accuracy, 86% [54 of 63]). In gastroenteropancreatic NET (n = 45), sensitivity was 94% (17 of 18); specificity was 89% (24 of 27); PPV was 85% (17 of 20); NPV was 96% (24 of 25); and accuracy was 91% (41 of 45). Two blinded readers achieved sensitivity of 79% (23 of 29) and 76% (22 of 29); specificity of 85% (29 of 34) and 94% (32 of 34) (κ = 0.80); and accuracy of 83% and 86%.. (68)Ga-DOTATATE PET/CT is accurate in detection of recurrent NET. Blinded PET/CT review markedly decreased sensitivity, underlining importance of considering clinical parameters in NET recurrence. Present results must be further validated to substantiate use of (68)Ga-DOTATATE PET/CT in routine follow-up after curative resection of NET.

Topics: Adult; Aged; Aged, 80 and over; Female; Humans; Male; Middle Aged; Multimodal Imaging; Neoplasm Recurrence, Local; Neuroendocrine Tumors; Organometallic Compounds; Positron-Emission Tomography; Predictive Value of Tests; Retrospective Studies; Sensitivity and Specificity; Tomography, X-Ray Computed

To evaluate the diagnostic accuracy of dynamic-contrast-enhanced (DCE) MRI in comparison to both (18)F-FDG- and (68)Ga-DOTATATE-PET/CT in patients with liver metastases of neuroendocrine neoplasms (NEN).. Thirty-two patients with hepatic metastases from NEN were examined both in DCE-MRI and positron emission tomography/computed tomography (PET/CT), using either (18)F-fluorodeoxyglucose ((18)F-FDG) or (68)Ga-DOTATATE as tracer. DCE-MRI was performed at 3 Tesla with Gd-EOB-DTPA acquiring 48 slices every 2.2 s for 5 min. Three regions of interest (ROIs) representing liver background and liver metastases were defined in fat-saturated T1w three-dimensional GRE MRI sequences in the hepatobiliary phase. Corresponding ROIs were then defined in the DCE-MRI- and in the PET/CT-dataset. Area under the curve (AUC) was calculated for the differentiation between metastases and liver background for DCE-MRI and PET-CT parameters.. AUC was very high for SUVmean (mean standardized uptake value) derived from (68)Ga-DOTATATE- (AUC = 0.966), and (18)F-FDG-PET/CT (AUC = 0.989). For DCE-MRI parameters, arterial flow fraction and intracellular uptake fraction showed the highest AUCs (AUC = 0.826, AUC = 0.819, respectively). The combination of those two had an AUC of 0.949. The combination of DCE-MRI and PET-CT parameters resulted in the highest AUC.. Both PET/CT parameters and DCE-MRI perfusion parameters show a high diagnostic accuracy in the distinction between liver metastases and liver tissue. Our data suggest that both modalities provide complementary information.

Topics: Adult; Aged; Aged, 80 and over; Contrast Media; Female; Fluorodeoxyglucose F18; Gadolinium DTPA; Humans; Liver Neoplasms; Magnetic Resonance Imaging; Male; Middle Aged; Multimodal Imaging; Neuroendocrine Tumors; Organometallic Compounds; Positron-Emission Tomography; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity; Tomography, X-Ray Computed

The present work was aimed at the formulation and evaluation of freeze-dried kits of 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA)-peptides for the preparation of (68)Ga-labelled peptides for PET imaging of neuroendocrine tumours. The (68)GaCl3 was obtained from the locally produced nanoceria-PAN, composite-sorbent-based (68)Ge/(68)Ga generator.. Single vial kits of somatostatin analogues DOTA-[Tyr(3)]-octreotide (DOTA-TOC), DOTA-[NaI(3)]-octreotide (DOTA-NOC) and DOTA-Tyr(3)-Thre(8)-octreotide (DOTA-TATE) were formulated. Optimization of radiolabelling with (68)Ga from the in-house generator, characterization, long term evaluation of stability of kits and bioevaluation studies in animals was carried out.. DOTA-TOC, DOTA-NOC and DOTA-TATE kits could be successfully formulated. Consistently high radiochemical yields (>95 %) were obtained on radiolabelling with (68)Ga. The radiolabelled peptides exhibited excellent in vitro stability. Biodistribution studies in normal non-tumour bearing Swiss mice revealed fast clearance of activity via renal route as reported for the respective peptides.. Availability of ready to use DOTA-peptide kits in conjunction with (68)Ge/(68)Ga generators would pave way for the establishment of (68)Ga radiopharmacy, a long-felt need of the nuclear medicine community.

Topics: Animals; Cerium; Chemistry, Pharmaceutical; Chromatography, High Pressure Liquid; Freeze Drying; Gallium Radioisotopes; Mice; Neuroendocrine Tumors; Octreotide; Organometallic Compounds; Peptides; Positron-Emission Tomography; Reagent Kits, Diagnostic; Tissue Distribution

Over recent decades interest in diagnosis and treatment of neuroendocrine tumours (NET) has steadily grown. The basis for diagnosis and therapy of NET with radiolabelled somatostatin (hsst) analogues is the variable overexpression of hsst receptors (hsst1-5 receptors). We hypothesized that radiometal derivatives of DOTA-iodo-Tyr(3)-octreotide analogues might be excellent candidates for somatostatin receptor imaging. We therefore explored the diagnostic potential of (68)Ga-DOTA-iodo-Tyr(3)-octreotate [(68)Ga-DOTA,3-iodo-Tyr(3),Thr(8)]octreotide ((68)Ga-HA-DOTATATE; HA, high-affinity) compared to the established (68)Ga-DOTA-Tyr(3)-octreotate ((68)Ga-DOTATATE) in vivo.. The study included 23 patients with known somatostatin receptor-positive metastases from NETs, thyroid cancer or glomus tumours who were investigated with both (68)Ga-HA-DOTATATE and (68)Ga-DOTATATE. A patient-based and a lesion-based comparative analysis was carried out of normal tissue distribution and lesion detectability in a qualitative and a semiquantitative manner.. (68)Ga-HA-DOTATATE and (68)Ga-DOTATATE showed comparable uptake in the liver (SUVmean 8.9 ± 2.2 vs. 9.3 ± 2.5, n.s.), renal cortex (SUVmean 13.3 ± 3.9 vs. 14.5 ± 3.7, n.s.) and spleen (SUVmean 24.0 ± 6.7 vs. 22.9 ± 7.3, n.s.). A somewhat higher pituitary uptake was found with (68)Ga-HA-DOTATATE (SUVmean 6.3 ± 1.8 vs. 5.4 ± 2.1, p < 0.05). On a lesion-by-lesion basis a total of 344 lesions were detected. (68)Ga-HA-DOTATATE demonstrated 328 lesions (95.3% of total lesions seen), and (68)Ga-DOTATATE demonstrated 332 lesions (96.4%). The mean SUVmax of all lesions was not significantly different between (68)Ga-HA-DOTATATE and (68)Ga-DOTATATE (17.8 ± 11.4 vs. 16.7 ± 10.7, n.s.).. Our analysis demonstrated very good concordance between (68)Ga-HA-DOTATATE and (68)Ga-DOTATATE PET data. As the availability and use of (68)Ga-HA-DOTATATE is not governed by patent restrictions it may be an attractive alternative to other (68)Ga-labelled hsst analogues.

Topics: Adult; Aged; Aged, 80 and over; Female; Humans; Male; Middle Aged; Neuroendocrine Tumors; Organometallic Compounds; Positron-Emission Tomography; Radiopharmaceuticals; Thyroid Neoplasms; Tissue Distribution

The objective of this study was to assess the relevance of physiological (68)Ga-DOTATATE PET/CT findings in the pancreas guided by morphological imaging (MI) in comparison with pathological tumour uptake in patients with neuroendocrine tumours (NETs).. A total of 138 patients with pancreatic NET (pNET; n=38) or non-pNET (n=100) underwent (68)Ga-DOTATATE PET/CT. Pancreatic regions with intensity higher than background were localized with anatomical reference support [head/uncinate process (HUP); body/tail (BT)] and classified as tumour, suspicious or physiological. Maximum standardized uptake value (SUV(max)) was assessed in all regions. PET/CT findings were compared with MI results.. Physiological uptake was seen in 10/38 pNETs (SUV(max) range, mean±SD and median in HUP and BT: 2.4-12.7, 5.9±3.2 and 4.6; 3.8-6.6, 6.6±2.5 and 5.6, respectively). A total of 18/38 showed high uptake (SUV(max) range, mean±SD and median in HUP and BT: 6.9-50, 26.9±13.5 and 27; 10-151, 32.2±36 and 19.4, respectively) with abnormal MI results. Among 10/38 patients we observed a total of n=15 discordant findings between PET/CT and MI: two lesions detected by MI did not correspond to any pathologial uptake on PET/CT, five suspicious uptake in the HUP did not correspond to any abnormal finding on MI, one HUP suspicious uptake correspondend to a lymphadenopaty on MI and seven suspicious BT uptake correspondend to calcification (1/6), cystic lesions (3/6), lesion different form the one detected by PET/CT (1/6) or negative findings (2/6) on MI. Among the 100 patients with non-pNETs, 97 showed homogeneous uptake and three had suspicious pancreatic uptake without concordant findings on MI.. Physiological pancreatic uptake of (68)Ga-DOTATATE showed low SUV(max), whereas tumours showed higher SUV(max); this is in agreement with previously published data. Equivocal findings showed SUV(max) in the grey area between physiological and pathological ranges, and for these lesions MI and histological confirmation are required for final diagnosis.

Topics: Adult; Aged; Aged, 80 and over; Biological Transport; Female; Humans; Male; Middle Aged; Multimodal Imaging; Neuroendocrine Tumors; Organometallic Compounds; Pancreas; Pancreatic Neoplasms; Positron-Emission Tomography; Reproducibility of Results; Tomography, X-Ray Computed; Young Adult

There is little evidence regarding the role of (68)Ga-DOTATATE PET/CT for the identification of primary tumors in patients with metastatic neuroendocrine carcinoma of unknown primary. The aim of this study is to assess the value of this technique in the mentioned clinical scenario.. We retrospectively studied twenty-nine patients (mean age 59.5 ± 10.6 years; female 17) with pathologically proven neuroendocrine metastases. In all cases conventional imaging was negative for primary tumor identification. (68)Ga-DOTATATE PET/CT was performed with a mean dose of 104.2 ± 18.8 MBq, using a 64-slice PET/CT with time-of-flight correction. A team of an experienced radiologist and a nuclear medicine physician evaluated the images. The maximum SUV (SUVm) was measured in all abnormal foci. Histopathology (when available) and/or clinical follow-up with correlative imaging was considered as reference standard.. (68)Ga-DOTATATE PET/CT identified the primary tumor in 17/29 (59%) patients in the following locations: pancreas (n = 7), ileum (n = 7), duodenum (n = 1), colon (n = 1) and stomach (n = 1). In this population a significant correlation was found between SUVm of primary tumor and metastases (r = 0.815, P < 0.0001). Furthermore, additional sites of unsuspected metastases were demonstrated in 9 patients of this group and in 6 patients in whom no primary tumor was localized, mainly in lymph nodes and mesentery. Pathology confirmation was obtained in 7 patients who underwent surgery, whereas in the remaining 10 patients, correlative imaging and follow-up confirmed primary tumor localization.. (68)Ga-DOTATATE PET/CT is a clinically useful imaging technique for the localization of primary tumors in patients with neuroendocrine metastatic carcinoma of unknown origin with the potential of having a significant impact in patient management and therapy planning.

Topics: Adult; Aged; Female; Humans; Male; Middle Aged; Multimodal Imaging; Neoplasms, Unknown Primary; Neuroendocrine Tumors; Organometallic Compounds; Positron-Emission Tomography; Retrospective Studies; Tomography, X-Ray Computed

Gastric neuroendocrine tumors (g-NETs), which originate from gastric enterochromaffin-like (ECL) mucosal cells and account for 2.4% of all carcinoids, are increasingly recognized due to expanding indications of upper gastrointestinal endoscopy. Often silent and benign, g-NETs may however, be aggressive and sometimes they mimic the course of gastric adenocarcinoma. Current nosography distinguishes those occurring in chronic conditions with hypergastrinemia, as the type 1 associated with chronic atrophic gastritis, and the type 2 associated with Zollinger-Ellison syndrome in MEN1. Conversely, type 3 and 4 (according to some authors) are unrelated to hypergastrinemia and are frequently malignant, with a propension to develop distant metastases. While there is a general agreement concerning the treatment of malignant gastric neuroendocrine tumors, for types 1 and 2, current possibilities include surveillance, endoscopic polypectomy, surgical excision, associated or not with surgical antrectomy, or total gastrectomy. This report, based on our clinical experience, discusses how the size, number, depth, histological grading, staging with CT, MRI, and the use of recently developed somatostatin receptor tracers (68Ga-DOTATATE, 68Ga-DOTA-TOC) could allow the correct identification of a benign or malignant propensity of an individual tumor, thus avoiding underestimation or overtreatment of these uncommon neoplasms.

Topics: Aged; Diagnosis, Differential; Female; Gallium; Gastrectomy; Humans; Male; Middle Aged; Neuroendocrine Tumors; Octreotide; Organometallic Compounds; Positron-Emission Tomography; Stomach Neoplasms; Tomography, X-Ray Computed

68Ga-labelled compounds are increasingly used for somatostatin-receptor scintigraphy because of their favourable biokinetic properties, a higher tumour-to-background contrast and higher diagnostic accuracy compared to the gamma-emitting tracer 111In-DTPA-octreotide. Recently, we have introduced the new tracer 68Ga-DOTA-3-iodo-Tyr3-Thr8-octreotide (68Ga-HA-DOTATATE). The present study demonstrates the biodistribution and radiation dosimetry of this tracer in humans.. Seven men were enrolled in this analysis. Every patient underwent a 20 min dynamic PET scan after intravenous injection of about 114 ± 9 MBq of 68Ga-HA-DOTATATE. This was followed by two whole-body scans at 30 min p. i. and 120 min p. i. Blood radioactivity concentration was determined non-invasively from a ROI drawn over the aorta. Urine was collected until the time of the last scan. Liver, spleen, kidneys and urinary bladder wall were included in the dosimetric estimation that was carried out with the software package OLINDA 1.0.. Physiological 68Ga-HA-DOTATATE uptake was observed in the pituitary gland, thyroid, salivary glands, liver, spleen, kidneys, urinary bladder, adrenals and intestine. Organs with the highest absorbed dose were spleen (0.26 ± 0.11 mSv/MBq), kidneys (0.14 ± 0.03 mSv/MBq) and liver (0.12 ± 0.02 mSv/MBq).The estimated effective dose was 0.024 ± 0.001 mSv/MBq.. Our study demonstrates biokinetics and radiation exposure of the 68Ga-labelled tracer HA-DOTATATE to be comparable to other 68Ga-labelled SSR analogues in clinical use.

Topics: Absorption, Radiation; Adult; Aged; Humans; Middle Aged; Neuroendocrine Tumors; Organ Specificity; Organometallic Compounds; Positron-Emission Tomography; Radiation Dosage; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity; Tissue Distribution; Whole-Body Counting

The aim of this study was to define the frequency of neuroendocrine neoplasia (NEN) metastasis sites based on the primary lesion and create a database of SUVmax as a marker of human SSTR (somatostatin receptors) expression by semiquantitative analysis in vivo Ga DOTATATE PET/CT.. Two hundred forty-five patients, 89 men and 156 women (mean [SD] age, 56.1 [12.8]), were imaged 60 to 70 minutes after 120 to 200 MBq (3.2-5.4 mCi) Ga DOTATATE injection using a Siemens Medical Solutions Biograph 64 PET/CT TruePoint. Visual assessments were made using a multimodality workstation, and sites of increased uptake were recorded. Pathological Ga DOTATATE uptake was quantified using semiquantitative analysis (SUVmax).. In patients with unknown primary tumors, Ga DOTATATE PET/CT revealed primary location in 92% (pancreas, 47%; intestines, 28%; and lung, 17%).Metastases, with respect to the primary sites, were predominantly in the liver (33% vs 49% vs 40%), lymph nodes (24% vs 34% vs 25%), and bone (10% vs 20% vs 30%). The SUVmax of metastases (mean [SD]) was highest in the liver (28.7 [23.5]), followed by the adrenal glands (24.7 [9.7]), bone (24.1 [36.8]), lymph nodes (22.5 [24.5]), pancreas (24.9 [28.1]), peritoneum (21.9 [24]), and the brain (4.6 [2.9]).. Ga DOTATATE PET/CT is very useful in the localization of NEN primary tumors. Ga DOTATATE PET/CT allows for visualizations of bone and lymph node metastases, not detected by any other modalities, which provides better staging and changes the clinical decision in approximately one third of patients.Our study shows that pancreatic NEN presented statistically a significantly lower frequency of bone metastases in comparison to lung and intestinal NEN. No significant frequency of metastases in the liver and lymph nodes based on primary tumors was observed.

Topics: Adult; Aged; Data Interpretation, Statistical; Female; Humans; Male; Middle Aged; Multimodal Imaging; Neoplasm Metastasis; Neuroendocrine Tumors; Organometallic Compounds; Positron-Emission Tomography; Radiopharmaceuticals; Tomography, X-Ray Computed

Radioguided surgery using 68-gallium labelled somatostatin analogues is a promising method for detection of small, intra-abdominal, neuroendocrine neoplasm (NEN). However, due to high background activity (physiological uptake in e.g. spleen, adrenal glands and kidneys) tumours of the tail and body of pancreas might be impossible to detect with hand-held gamma probe. Therefore a new concept of intraoperative PET/CT scan of the resected tissue can be helpful in determining whether the tumour has been excised within the margins of healthy tissue. A 71-year-old woman with primary, non-metastatic NEN of the tail of pancreas is described. The tumour was diagnosed using MRI and PET/CT scan. Before operation patient was administered intravenously 80 MBq of ⁶⁸Ga-DOTATATE. The surgery procedure was performed 60-180 minutes post injection. During the procedure pancreas was visualized, but the tumour could not be localized neither with palpation nor gamma probe. The tail of the pancreas was resected en bloc with spleen and adjacent lymph nodes. PET/CT scan of the tissue specimen was performed immediately followed by pathological examination. PET/CT scan of the resected tissue showed moderate activity in the tail of pancreas, and a small focus of high activity in the tail. Area of high SSTR expression in the tail corresponded with preoperative findings in MRI and whole-body PET/CT. Histopathological examination of the specimen confirmed the presence of neuroendocrine tumour grade 1. Immediate PET/CT scan of the surgical specimen can bring new quality to intraoperative assessment of completeness of resection of neuroendocrine tumours.

Topics: Aged; Female; Humans; Multimodal Imaging; Neuroendocrine Tumors; Organometallic Compounds; Pancreatic Neoplasms; Positron-Emission Tomography; Surgery, Computer-Assisted; Tomography, X-Ray Computed

There are different metabolic imaging methods, various tracers, and emerging anatomic modalities to stage neuroendocrine tumor (NET). We aimed to compare NET lesion detectability among (99m)Tc-hydrazinonicotinamide (HYNIC)-octreotide (somatostatin receptor scintigraphy [SSRS]) SPECT/CT, (68)Ga-DOTATATE PET/CT, and whole-body diffusion-weighted MR imaging (WB DWI).. Nineteen consecutive patients (34-77 y old; mean, 54.3 ± 10.4 y old; 10 men and 9 women) underwent SSRS SPECT/CT, (68)Ga-DOTATATE PET/CT, and WB DWI. Images were acquired with a maximum interval of 3 mo between them and were analyzed with masking by separate teams. Planar whole-body imaging and SPECT/CT were performed from thorax to pelvis using a double-head 16-slice SPECT/CT scanner 4 h after injection of 111-185 MBq of (99m)Tc-HYNIC-octreotide. (68)Ga-DOTATATE PET/CT was performed from head to feet using a 16-slice PET/CT scanner 45 min after injection of 185 MBq of tracer. WB DWI was performed in the coronal plane using a 1.5-T scanner and a body coil. The standard method of reference for evaluation of image performance was undertaken: consensus among investigators at the end of the study, clinical and imaging follow-up, and biopsy of suggestive lesions.. McNemar testing was applied to evaluate the detectability of lesions using (68)Ga-DOTATATE PET/CT in comparison to SSRS SPECT/CT and WB DWI: a significant difference in detectability was noted for pancreas (P = 0.0455 and P = 0.0455, respectively), gastrointestinal tract (P = 0.0455 and P = 0.0455), and bones (P = 0.0082 and P = 0.0082). Two unknown primary lesions were identified solely by (68)Ga-DOTATATE PET/CT. (68)Ga-DOTATATE PET/CT, SSRS SPECT/CT, and WB DWI demonstrated, respectively, sensitivities of 0.96, 0.60, and 0.72; specificities of 0.97, 0.99, and 1.00; positive predictive values of 0.94, 0.96, and 1.00; negative predictive values of 0.98, 0.83, and 0.88; and accuracies of 0.97, 0.86, and 0.91.. (68)Ga PET/CT seems to be more sensitive for detection of well-differentiated NET lesions, especially for bone and unknown primary lesions. NET can be staged with (68)Ga-DOTATATE PET/CT. WB DWI is an efficient new method with high accuracy and without ionizing radiation exposure. SSRS SPECT/CT should be used only when (68)Ga-DOTATATE PET/CT and WB DWI are not available.

Topics: Adult; Aged; Algorithms; Biopsy; Female; Humans; Hydrazines; Magnetic Resonance Imaging; Male; Middle Aged; Neuroendocrine Tumors; Nicotinic Acids; Octreotide; Organometallic Compounds; Positron-Emission Tomography; Prospective Studies; Technetium; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed; Whole Body Imaging

Gastroenteropancreatic neuroendocrine tumors (GEPNETs) are indolent neoplasms presenting unpredictable and unusual biologic behavior that causes many clinical challenges. Tumor size, existence of metastasis, and histopathologic classification remain incapable in terms of treatment decision and prognosis estimation. This study aimed to compare (68)Ga-DOTATATE and (18)F-FDG PET/CT in GEPNETs and to investigate the relation between the complementary PET/CT results and histopathologic findings in the management of therapy, particularly in intermediate-grade patients.. The relation between complementary (68)Ga-DOTATATE and (18)F-FDG PET/CT results of 27 GEPNET patients (mean age, 56 y; age range, 33-79 y) and histopathologic findings was evaluated according to grade and localization using standardized maximum uptake values and Ki67 indices. Grade 2 (G2) patients were further evaluated in 2 groups as G2a (3%-9%) and G2b (10%-20%) according to Ki67 indices.. The sensitivity of (68)Ga-DOTATATE and (18)F-FDG PET/CT was 95% and 37%, respectively, and the positive predictive values were 93.8% and 36.2%, respectively. The sensitivity in detecting liver metastasis, lymph nodes, bone metastasis, and primary lesion was 95%, 95%, 90%, and 93% for (68)Ga-DOTATATE and 40%, 28%, 28%, and 75% for (18)F-FDG, respectively. Statistically significant differences were found between grades 1-2, 2a-2b, and 1-2b with respect to (68)Ga-DOTATATE PET/CT as well as between 1-2a and 1-2b with respect to (18)F-FDG PET/CT. However, no statistical differences were found between 1 and 2a (P > 0.05) for (68)Ga-DOTATATE and 2a and 2b (P = 0.484) for (18)F-FDG. The impact of the combined (18)F-FDG and (68)Ga-DOTATATE PET/CT on the therapeutic decision was 59%.. Combined (68)Ga-DOTATATE and (18)F-FDG PET/CT is helpful in the individual therapeutic approach of GEPNETs and can overcome the shortcomings of histopathologic grading especially in intermediate-grade GEPNETs.

Topics: Adult; Aged; Female; Fluorodeoxyglucose F18; Humans; Image Processing, Computer-Assisted; Intestinal Neoplasms; Ki-67 Antigen; Male; Middle Aged; Multimodal Imaging; Neoplasm Metastasis; Neuroendocrine Tumors; Organometallic Compounds; Pancreatic Neoplasms; Positron-Emission Tomography; Prospective Studies; Sensitivity and Specificity; Stomach Neoplasms; Tomography, X-Ray Computed

Topics: Female; Fluorodeoxyglucose F18; Humans; Intestinal Neoplasms; Male; Neuroendocrine Tumors; Organometallic Compounds; Pancreatic Neoplasms; Positron-Emission Tomography; Stomach Neoplasms; Tomography, X-Ray Computed

The aim of the study was to evaluate contrast-enhanced MRI, diffusion-weighted MRI (DW MRI), and (68)Ga-DOTATATE positron emission tomography (PET)/CT in the detection of intermediate to well-differentiated neuroendocrine tumors (NET) of the pancreas.. Eighteen patients with pathologically proven pancreatic NET who underwent MRI including DW MRI and PET/CT within 6 weeks of each other were included in this retrospective study. Two radiologists evaluated T2-weighted (T2w), T2w + DW MRI, T2w + contrast-enhanced T1-weighted (CE T1w) MR images, and PET/CT for NET detection. The sensitivity and level of diagnostic confidence were compared among modalities using McNemar's test and a Wilcoxon signed rank test. Apparent diffusion coefficients (ADC) of pancreatic NETs and normal pancreatic tissue were compared with Student's t test.. Of the NETs, 8/23 (34.8 %) and 9/23 (39.1 %) were detected on T2w images by observers 1 and 2, respectively. Detection rates improved significantly by combining T2w images with DW MRI (observer 1: 14/23 = 61 %; observer 2: 15/23 = 65.2 %; p < 0.05) or CE T1w images (observer 1: 14/23 = 61 %; observer 2: 15/23 = 65.2 %; p < 0.05). Detection rates of pancreatic NET with PET/CT (both observers: 23/23 = 100 %) were statistically significantly higher than with MRI (p < 0.05). The mean ADC value of NET (1.02 ± 0.26 × 10(-3) mm(2)/s) was statistically significantly lower than that of normal pancreatic tissue (1.48 ± 0.39 × 10(-3) mm(2)/s).. DW MRI is a valuable adjunct to T2w imaging and comparable to CE T1w imaging in pancreatic NET detection, quantitatively differentiating between NET and normal pancreatic tissue with ADC measurements. (68)Ga-DOTATATE PET/CT is more sensitive than MRI in the detection of pancreatic NET.

Topics: Abdomen; Adult; Aged; Diffusion Magnetic Resonance Imaging; Female; Humans; Image Processing, Computer-Assisted; Male; Middle Aged; Models, Statistical; Neuroendocrine Tumors; Observer Variation; Organometallic Compounds; Pancreatic Neoplasms; Reproducibility of Results; Retrospective Studies

A 62-year-old female patient with suspected insulinoma underwent 68Ga DOTA-TATE PET/CT for characterization and staging. This demonstrated a focus of uptake in the pancreas and 3 foci of uptake in the spine. An MRI of the spine performed to further characterize the lesions revealed the presence of a meningioma and degenerative changes, both of which showed 68Ga DOTA-TATE uptake. A vertebral metastasis seen on PET was occult on CT and MRI. A vertebral hemangioma had no discrete tracer uptake. Awareness of sources of error in interpreting 68Ga DOTA-TATE scans is important in order to avoid pitfalls.

Topics: Female; Humans; Magnetic Resonance Imaging; Middle Aged; Multimodal Imaging; Neoplasm Staging; Neuroendocrine Tumors; Organometallic Compounds; Positron-Emission Tomography; Spinal Neoplasms; Tomography, X-Ray Computed

Recent studies have suggested that PET imaging with Ga-68-labelled DOTA-somatostatin analogues such as octreotide and octreotate is useful in diagnosing neuroendocrine tumours (NETs) and has superior value over both computed tomography and planar and SPECT somatostatin receptor scintigraphy.. The aim of the present study was to evaluate the role of Ga-68 DOTA-lanreotide (Ga-68-DOTA-LAN) in patients with somatostatin receptor (sst)-expressing tumours and to compare the results of Ga-68 DOTA-D-Phe1-Tyr3-octreotate (Ga-68-DOTA-TATE) in the same patient population.. Twelve patients with NETs who were referred to our department for somatostatin receptor scintigraphy were included in the study. There were four patients with well-differentiated neuroendocrine tumour (WDNET) grade 1, two patients with WDNET grade 2, and three patients with poorly differentiated neuroendocrine carcinoma (PDNEC) grade 3. There was also one patient with medullary thyroid cancer, one patient with meningioma and one patient with MEN-1. All patients underwent two consecutive PET imaging studies with Ga-68-DOTA-TATE and Ga-68 DOTA-LAN. All images were evaluated visually, and maximum standardized uptake value was calculated for quantitative evaluation.. On visual examination of maximum intensity projection images, GA-68 DOTA-LAN was seen to have high background activity and high bone marrow uptake. Both tracers defined 67 lesions. Ga-68 DOTA-TATE images revealed 63 (94%) clearly defined lesions, missing four lesions. In contrast, Ga-68 DOTA-LAN images defined only 23 (44%) lesions, missing 44 (56%) lesions. Thirty-two bone lesions were detected on Ga-68-DOTA-TATE images. Among them, only 11 (34%) were positive on Ga-68 DOTA-LAN images, whereas 21 (66%) were negative. When we evaluated liver, mediastinum and gastrointestinal tract lesions, Ga-68 DOTA-LAN was seen to be positive for 12 (34%) lesions and negative for 23 (66%) lesions.. Although the results are preliminary, the image quality obtained by Ga-68-DOTA-TATE seems to be superior to that obtained by Ga-68 DOTA-LAN. With its significantly higher lesion uptake and higher ability to detect lesions, Ga-68-DOTA-TATE seems to be a better radioligand compared with Ga-68-DOTA-LAN for the diagnosis of NETs.

Topics: Adult; Aged; Female; Gene Expression Regulation, Neoplastic; Heterocyclic Compounds, 1-Ring; Humans; Male; Middle Aged; Multimodal Imaging; Neuroendocrine Tumors; Organometallic Compounds; Peptides, Cyclic; Positron-Emission Tomography; Receptors, Somatostatin; Somatostatin; Tomography, X-Ray Computed

(68)Ga-DOTATOC and (68)Ga-DOTATATE are 2 radiolabeled somatostatin analogs for in vivo diagnosis of neuroendocrine tumors with PET. The aim of the present work was to measure their comparative biodistribution and radiation dosimetry.. Ten patients diagnosed with neuroendocrine tumors were included. Each patient underwent a 45-min dynamic and 3 whole-body PET/CT scans at 1, 2, and 3 h after injection of each tracer on consecutive days. Absorbed doses were calculated using OLINDA/EXM 1.1.. Data from 9 patients could be included in the analysis. Of the major organs, the highest uptake at 1, 2, and 3 h after injection was observed in the spleen, followed by kidneys and liver. For both tracers, the highest absorbed organ doses were seen in the spleen and urinary bladder wall, followed by kidney, adrenals, and liver. The absorbed doses to the liver and gallbladder wall were slightly but significantly higher for (68)Ga-DOTATATE. The total effective dose was 0.021 ± 0.003 mSv/MBq for both tracers.. The effective dose for a typical 100-MBq administration of (68)Ga-DOTATATE and (68)Ga-DOTATOC is 2.1 mSv for both tracers. Therefore, from a radiation dosimetry point of view, there is no preference for either tracer for PET/CT evaluation of somatostatin receptor-expressing tumors.

Topics: Adult; Aged; Female; Humans; Male; Middle Aged; Multimodal Imaging; Neuroendocrine Tumors; Octreotide; Organometallic Compounds; Positron-Emission Tomography; Radiometry; Tissue Distribution; Tomography, X-Ray Computed; Whole Body Imaging

Topics: Female; Humans; Hypercholesterolemia; Inflammation; Male; Middle Aged; Multimodal Imaging; Neuroendocrine Tumors; Organometallic Compounds; Plaque, Atherosclerotic; Positron-Emission Tomography; Radiopharmaceuticals; Radiotherapy; Receptors, Somatostatin; Retrospective Studies; Tomography, X-Ray Computed

(68)Gallium-PET ((68)Ga-PET) agents have significant clinical promise. The radionuclide can be produced from a (68)Ge/(68)Ga generator on site and is a convenient alternative to cyclotron-based PET isotopes. The short half-life of (68)Ga permits imaging applications with sufficient radioactivity while maintaining patient dose to an acceptable level. Furthermore, due to superior resolution, (68)Ga-PET agents have the ability to replace current SPECT agents in many applications. This article outlines the upcoming agents and challenges faced during the translational development of (68)Ga agents.

Topics: Amine Oxidase (Copper-Containing); Cell Adhesion Molecules; Gallium Radioisotopes; Glucagon-Like Peptide 1; Half-Life; Insulinoma; Neuroendocrine Tumors; Octreotide; Oligopeptides; Organometallic Compounds; Positron-Emission Tomography; Radionuclide Generators; Radiopharmaceuticals; Receptors, Bombesin; Receptors, Somatostatin; Single-Domain Antibodies; Somatostatin; Vascular Endothelial Growth Factor A

Tumour sequestration of radiotracer may lead to decreased bioavailability in healthy tissue resulting in lower absorbed radiation dose to critical organs. This study aims to assess the impact of disease burden, body habitus and urinary excretion on the biodistribution of (68)Ga-DOTA-octreotate.. Ten patients with highly varied burden of somatostatin receptor-positive neuroendocrine tumour on (68)Ga-DOTA-octreotate positron emission tomography (PET)/CT were selected. Volumes of interest were drawn to derive the average uptake of renal parenchyma, spleen and body background, as well as to compute the fraction of injected activity sequestered in tumour and excreted in urine. Uptake values were assessed for correlation with tumour sequestration, weight, lean body weight, body surface area and urinary excretion.. There was a trend for tumour sequestration, body habitus and urinary excretion to inversely influence all healthy tissue uptake values. In particular, renal uptake, splenic intensity and background soft tissue activity were all significantly correlated to composite factors combining tumour sequestration with body habitus and renal excretion. When combined with body habitus index or a body habitus index and renal excretion, tumour sequestration was strongly and significantly correlated inversely with renal uptake.. Our results suggest that tumour sequestration of (68)Ga-DOTA-octreotate is a major factor leading to a sink effect that decreases activity concentration in healthy organs such as the kidney. However, body habitus and renal function also influence tissue biodistribution, in a synergistic fashion. Compared with a fixed-dose peptide receptor radionuclide therapy protocol, an adjusted-dose regimen tailored to tumour burden, body habitus and renal function may allow greater radiation dose to individual lesions without substantially adding to toxicity in normal tissues.

Topics: Adult; Aged; Female; Humans; Injections; Linear Models; Male; Middle Aged; Neuroendocrine Tumors; Organometallic Compounds; Positron-Emission Tomography; Receptors, Somatostatin; Retrospective Studies

The aim of the study was to compare sequential (177)Lu-DOTA-TATE planar scans ((177)Lu-DOTA-TATE) in patients with metastasized neuroendocrine tumours (NET) acquired during peptide receptor radionuclide therapy (PRRT) for dosimetry purposes with the pre-therapeutic (68)Ga-DOTA-TATE positron emission tomography (PET)/CT ((68)Ga-DOTA-TATE) maximum intensity projection (MIP) images obtained in the same patients concerning the sensitivity of the different methods.. A total of 44 patients (59 ± 11 years old) with biopsy-proven NET underwent (68)Ga-DOTA-TATE and (177)Lu-DOTA-TATE imaging within 7.9 ± 7.5 days between the two examinations. (177)Lu-DOTA-TATE planar images were acquired at 0.5, 2, 24, 48 and 72 h post-injection; lesions were given a score from 0 to 4 depending on the uptake of the radiopharmaceutical (0 being lowest and 4 highest). The number of tumour lesions which were identified on (177)Lu-DOTA-TATE scans (in relation to the acquisition time after injection of the therapeutic dose as well as with regard to the body region) was compared to those detected on (68)Ga-DOTA-TATE studies obtained before PRRT.. A total of 318 lesions were detected; 280 (88%) lesions were concordant. Among the discordant lesions, 29 were (68)Ga-DOTA-TATE positive and (177)Lu-DOTA-TATE negative, whereas 9 were (68)Ga-DOTA-TATE negative and (177)Lu-DOTA-TATE positive. The sensitivity, positive predictive value and accuracy for (177)Lu-DOTA-TATE as compared to (68)Ga-DOTA-TATE were 91, 97 and 88%, respectively. Significantly more lesions were seen on the delayed (72 h) (177)Lu-DOTA-TATE images (91%) as compared to the immediate (30 min) images (68%). The highest concordance was observed for bone metastases (97%) and the lowest for head/neck lesions (75%). Concordant lesions (n = 77; mean size 3.8 cm) were significantly larger than discordant lesions (n = 38; mean size 1.6 cm) (p < 0.05). No such significance was found for differences in maximum standardized uptake value (SUV(max)). However, concordant liver lesions with a score from 1 to 3 in the 72-h (177)Lu-DOTA-TATE scan had a lower SUV(max) (n = 23; mean 10.9) than those metastases with a score of 4 (n = 97; mean SUV(max) 18) (p < 0.05).. Although (177)Lu-DOTA-TATE planar dosimetry scans exhibited a very good sensitivity for the detection of metastases, they failed to pick up 9% of lesions seen on the (68)Ga-DOTA-TATE PET/CT. Three-dimensional dosimetry using single photon emission computed tomography/CT could be applied to investigate this issue further. Delayed (72 h) images are most suitable for drawing regions of interest for dosimetric calculations.

Topics: Adult; Aged; Aged, 80 and over; Female; Humans; Male; Middle Aged; Multimodal Imaging; Neoplasm Metastasis; Neuroendocrine Tumors; Octreotide; Organometallic Compounds; Positron-Emission Tomography; Radiometry; Receptors, Peptide; Retrospective Studies; Time Factors; Tomography, X-Ray Computed; Young Adult

Ga-68 DOTATATE (Ga-octreotate, GaTate) positron emission tomography (PET)/CT has multiple advantages compared with conventional and In-111 octreotide imaging for neuroendocrine tumours and other somatostatin-receptor expressing tumours. This study assesses the management impact of incremental diagnostic information obtained from this technique compared with conventional staging.. Fifty-nine GaTate PET/CT studies were performed over an 18-month period (52 proven or suspected gastro-entero-pancreatic or bronchial neuroendocrine tumours and seven neural crest/mesenchymal tumours). A retrospective blinded review was performed on the number of abnormalities (1, 2-5 or >5) within defined regions with comparison to conventional imaging to assess incremental diagnostic information. Subsequent management impact (high, moderate or low) was determined by clinical review and follow up to assess pre-PET stage, treatment intent and post-PET management change.. Eighty-eight percent of GaTate studies were abnormal. Compared with conventional and In-111 octreotide imaging, additional information was provided by GaTate PET/CT in 68 and 83% of patients, respectively. Management impact was high (inter-modality change) in 47%, moderate (intra-modality change) in 10% and low in 41% (not assessable in 2%). High management impact included directing patients to curative surgery by identifying a primary site and directing patients with multiple metastases to systemic therapy.. GaTate PET/CT imaging provides additional diagnostic information in a high proportion of patients with consequent high management impact. GaTate PET/CT could replace (1)In-111 octreotide scintigraphy at centres where it is available given its superior accuracy, faster acquisition and lower radiation exposure. Rapid implementation could be achieved by allowing substitutional funding in the Medicare Benefit Schedule.

Topics: Adult; Aged; Female; Humans; Male; Middle Aged; Multimodal Imaging; Neoplasm Staging; Neuroendocrine Tumors; Organometallic Compounds; Positron-Emission Tomography; Receptors, Somatostatin; Retrospective Studies; Tomography, X-Ray Computed

Recent studies have suggested that positron emission tomography (PET) imaging with (68)Ga-labelled DOTA-somatostatin analogues (SST) like octreotide and octreotate is useful in diagnosing neuroendocrine tumours (NETs) and has superior value over both CT and planar and single photon emission computed tomography (SPECT) somatostatin receptor scintigraphy (SRS). The aim of the present study was to evaluate the role of (68)Ga-DOTA-1-NaI(3)-octreotide ((68)Ga-DOTANOC) in patients with SST receptor-expressing tumours and to compare the results of (68)Ga-DOTA-D-Phe(1)-Tyr(3)-octreotate ((68)Ga-DOTATATE) in the same patient population.. Twenty SRS were included in the study. Patients' age (n = 20) ranged from 25 to 75 years (mean 55.4 ± 12.7 years). There were eight patients with well-differentiated neuroendocrine tumour (WDNET) grade1, eight patients with WDNET grade 2, one patient with poorly differentiated neuroendocrine carcinoma (PDNEC) grade 3 and one patient with mixed adenoneuroendocrine tumour (MANEC). All patients had two consecutive PET studies with (68)Ga-DOTATATE and (68)Ga-DOTANOC. All images were evaluated visually and maximum standardized uptake values (SUV(max)) were also calculated for quantitative evaluation.. On visual evaluation both tracers produced equally excellent image quality and similar body distribution. The physiological uptake sites of pituitary and salivary glands showed higher uptake in (68)Ga-DOTATATE images. Liver and spleen uptake values were evaluated as equal. Both (68)Ga-DOTATATE and (68)Ga-DOTANOC were negative in 6 (30 %) patients and positive in 14 (70 %) patients. In (68)Ga-DOTANOC images only 116 of 130 (89 %) lesions could be defined and 14 lesions were missed because of lack of any uptake. SUV(max) values of lesions were significantly higher on (68)Ga-DOTATATE images.. Our study demonstrated that the images obtained by (68)Ga-DOTATATE and (68)Ga-DOTANOC have comparable diagnostic accuracy. However, (68)Ga-DOTATATE seems to have a higher lesion uptake and may have a potential advantage.

Topics: Adult; Aged; Female; Gene Expression Regulation, Neoplastic; Humans; Male; Middle Aged; Multimodal Imaging; Neuroendocrine Tumors; Organometallic Compounds; Positron-Emission Tomography; Receptors, Somatostatin; Retrospective Studies; Tomography, X-Ray Computed

In patients with suspected but yet not localized neuroendocrine tumors (NETs), early diagnosis or reliable exclusion is crucial for optimal individual prognosis and therapy. Despite recourse to several imaging modalities, the definite diagnosis of NET can be challenging. Therefore, we tested (68)Ga-DOTATATE PET/CT as a tool for improved diagnosis in a cohort of patients with suspected, nonlocalized NET.. (68)Ga-DOTATATE PET/CT recordings were obtained in 104 consecutive patients meeting at least one of the following criteria: clinical suspicion of NET (n = 70), elevated blood levels of tumor markers (n = 49), and image-based suspicion of NET (n = 53). The presence of NET was validated by histopathology (n = 49) or clinical follow-up of 107 ± 59 wk (n = 55).. In 36 of 104 patients (35%), NET was histologically verified, most frequently located in the small bowel (10/36), pancreas (8/36), lung (5/36), and stomach (2/36). Twelve patients had tumors of nonneuroendocrine origin, and 7 patients had benign tumors. (68)Ga-DOTATATE PET/CT identified NET in 29 of the 36 cases and excluded the presence of a NET in 61 of the 68 non-NET patients, indicating a sensitivity of 81% and specificity of 90%. The PET/CT gave a false-positive result in 7 patients and a false-negative in another 7 patients, indicating positive and negative predictive values of 81% and 90%, respectively, and an accuracy of 87%. Chromogranin A levels were significantly higher in both PET-positive patients (1,841 vs. 342 ng/mL; P < 0.05) and patients with verified NET (2,214 vs. 524 ng/mL; P < 0.05).. In patients with suspected NETs due to clinical symptoms, elevated levels of tumor markers, or indeterminate tumors suggestive of NET, (68)Ga-DOTATATE PET/CT is highly accurate, thus supporting its use in clinical routine diagnostics.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Child; Child, Preschool; Chromogranin A; Female; Humans; Infant; Male; Middle Aged; Multimodal Imaging; Neuroendocrine Tumors; Organometallic Compounds; Positron-Emission Tomography; Retrospective Studies; Sensitivity and Specificity; Tomography, X-Ray Computed; Young Adult

Synchronous malignant neoplasms in a single patient are well documented in the literature. It is also recognized that there is increasing incidence of synchronous non-neuroendocrine neoplasm in patients with neuroendocrine tumor (NET). We present a case, of a patient with synchronous colorectal cancer and pancreatic NET, both cancers presenting with liver metastasis. By using 18F-FDG PET and 68Ga-DOTATATE PET imaging, we showed 2 different tumor types within the liver, which was subsequently confirmed on liver biopsy. This case report shows the utility of molecular imaging using different PET peptides. These newer modalities are useful in understanding the biology of the NET and in determining the best patient management.

Topics: Biopsy; Colorectal Neoplasms; Diagnosis, Differential; Fluorodeoxyglucose F18; Humans; Liver Neoplasms; Male; Middle Aged; Neoplasms, Multiple Primary; Neuroendocrine Tumors; Organometallic Compounds; Pancreatic Neoplasms; Positron-Emission Tomography

A 37-year-old man complained of increasing severity and frequency of abdominal pain over a 2-year period. Initial contrast-enhanced computed tomography of the abdomen demonstrated diffuse enlargement of the pancreas associated with a filling defect in the portal vein, splenomegaly with wedge-shaped peripheral splenic hypodensities and multiple hepatic hypodensities. Findings were suggestive of a pancreatic malignancy complicated by hepatic metastases, splenic infarcts, and portal vein thrombosis. We describe the use of gallium-68 DOTA-DPhe1, Tyr3-octreotate positron emission tomography/computed tomography (Ga-68 DOTATATE PET/CT) in confirming the diagnosis of a pancreatic neuroendocrine tumor with portal vein tumor thrombosis.

Topics: Adult; Humans; Male; Neuroendocrine Tumors; Organometallic Compounds; Pancreatic Neoplasms; Portal Vein; Positron-Emission Tomography; Tomography, X-Ray Computed; Venous Thrombosis

Positron emission tomography (PET) combined with computer tomography (CT) using (68)Ga-DOTATATE is a promising method for the evaluation of patients with recognised or suspected neuroendocrine tumours (NET). The aim of this study was to assess the diagnostic value of (68)Ga-DOTATATE PET/CT in the visualisation of the expression of somatostatin receptors (SSTR) and identification of new lesions.. Between December 2009 and January 2011 ninety-seven patients with confirmed (88 cases) or suspected (9 cases) NET underwent (68)Ga DOTATATE PET/CT. The primary, confirmed or suspected, NET localizations were: GEP tumours--71 patients; medullary thyroid carcinoma--4 patients; cancer of an unknown primary--14 patients; and NET in other localisations--8 patients. PET/CT acquisitions were performed using standard techniques, 45 to 60 minutes after the intravenous injection of 111-185 MBq (68)Ga-DOTATATE.. (68)Ga-DOTATATE PET/CT detected the presence of lesions demonstrating the somatostatin receptor affinity in 50 of the 97 patients (51.5%) and was negative in 47 patients (48.5%). Among 14 patients with metastatic unknown primary cancer, in 5 patients (45.5%) the primary tumour site was identified, and in 4 patients with medullary thyroid cancer distant metastases with SSTR expression were localized in only one patient.. Our findings confirm the diagnostic role of (68)Ga-DOTATATE PET/CT as an accurate method of identifying primary tumours and distant metastases. It provides information on tumour cell receptors status, which has a significant bearing on planning target radionuclide therapy. Overall, (68)Ga-DOTATATE PET/CT can be used in staging, re-staging, and in regular follow up of oncology patients.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Female; Gene Expression Regulation, Neoplastic; Humans; Male; Middle Aged; Neuroendocrine Tumors; Organometallic Compounds; Positron-Emission Tomography; Receptors, Somatostatin; Retrospective Studies; Tomography, X-Ray Computed; Young Adult

Topics: Humans; Mesenteric Veins; Neuroendocrine Tumors; Organometallic Compounds; Pancreatic Neoplasms; Positron-Emission Tomography; Radiopharmaceuticals; Subtraction Technique; Tomography, X-Ray Computed; Venous Thrombosis

We measured the uptake of the somatostatin receptor ligand (68)Ga-[1,4,7,10-tetraazacyclododecane-N,N',N'',N'''-tetraacetic acid]-D-Phe(1),Tyr(3)-octreotate (DOTATATE) in the left anterior descending coronary artery (LAD) in association with calcified plaques (CPs) and cardiovascular risk factors.. Seventy consecutive tumor patients were examined by whole-body (68)Ga-DOTATATE contrast-enhanced PET/CT. Blood-pool-corrected standardized uptake value (target-to-background ratio) was measured in the LAD, and CT images were used to detect CP. Cardiovascular risk factors and history of prior cardiovascular events were recorded.. (68)Ga-DOTATATE uptake was detectable in the LAD of all patients. Target-to-background ratio in the LAD correlated significantly with the presence of CP (R = 0.34; P < 0.01), prior vascular events (R = 0.26; P < 0.05), and male sex (R = 0.29; P < 0.05), whereas CP correlated with these parameters but also with age (R = 0.34; P < 0.01) and hypertension (R = 0.25; P < 0.05).. In a series of oncologic patients, those with prior cardiovascular events and calcified atherosclerotic plaques showed significantly increased (68)Ga-DOTATATE uptake in the LAD, suggesting a potential role of this tracer for plaque imaging in the coronary arteries.

Topics: Adult; Aged; Aged, 80 and over; Calcium; Coronary Angiography; Coronary Artery Disease; Coronary Vessels; Female; Gallium Radioisotopes; Humans; Macrophages; Male; Middle Aged; Neuroendocrine Tumors; Organometallic Compounds; Positron-Emission Tomography; Radiopharmaceuticals; Retrospective Studies; Risk Factors; Tomography, X-Ray Computed

The immunohistochemical expression of somatostatin receptor (SSTR) subtype 2 was compared to quantitative (68)Ga-DOTATATE PET in neuroendocrine tumors (NET).. In 27 patients suffering from metastatic NET the expression of somatostatin receptors (SSTR, score 0-3) and the Ki-67 index were assessed. The immunohistochemical findings were compared with the (68)Ga-DOTATATE PET uptake in these tumors using the SUV(max) (standardized uptake value). Both values were compared with the Ki-67 proliferation index.. The SUV(max) in NET without SSTR expression was significantly lower compared to those with SSTR expression (p <0.05), even though 3 out of 5 NETs with a score of 0 showed a high uptake of (68)Ga-DOTATATE. The SUV(max) correlated significantly (r=0.40, p <0.05) with the score of immunohistochemical SSTR expression (negative, score 0, moderate, score 1 and high, scores 2 and 3). The Ki-67 index correlated inversely with the SSTR expression score (r=-0.42, p <0.05), but not significantly with the SUV(max) (r=-0.33, p=0.11).. (68)Ga-DOTATATE uptake was moderately correlated with the results of immunohistochemical SSTR analyses. However, SSTR negative NET may show high uptake of (68)Ga-DOTATATE.

Topics: Adult; Aged; Female; Gene Expression Profiling; Humans; Male; Middle Aged; Neuroendocrine Tumors; Organometallic Compounds; Positron-Emission Tomography; Radiopharmaceuticals; Receptors, Somatostatin; Reproducibility of Results; Sensitivity and Specificity; Tissue Distribution; Tomography, X-Ray Computed

(111)In-diethylenetriaminepentaacetic acid (DTPA)-octreotide scintigraphy is currently the nuclear medicine imaging modality of choice for identifying neuroendocrine tumors. However, there are cohorts of patients in whom scintigraphy findings are negative or equivocal. We evaluated the role of (68)Ga-DOTATATE PET in a selected group of patients with negative or weakly positive findings on (111)In-DTPA-octreotide scintigraphy to determine whether (68)Ga-DOTATATE PET is able to detect additional disease and, if so, whether patient management is altered.. Fifty-one patients with a histologically confirmed diagnosis of neuroendocrine tumors were included. Of the 51 patients, 35 who were negative and 16 equivocal for uptake on (111)In-DTPA-octreotide scintigraphy underwent (68)Ga-DOTATATE PET. Findings were compared using a region-by-region analysis. All findings were verified with CT or MRI. After (68)Ga-DOTATATE PET, all cases were reviewed to determine whether the (68)Ga-DOTATATE PET findings resulted in any alteration in management, in terms of suitability for peptide receptor therapy, somatostatin analogs, and surgery.. Of the 51 patients, 47 had evidence of disease on cross-sectional imaging or biochemically. (68)Ga-DOTATATE PET was positive in 41 of these 47 patients (87.2%). No false-positive lesions were identified. (68)Ga-DOTATATE PET detected 168 of the 226 lesions (74.3%) that were identified with cross-sectional imaging. (68)Ga-DOTATATE PET identified significantly more lesions than (111)In-DTPA-octreotide scintigraphy (P < 0.001). There was no correlation between (68)Ga-DOTATATE uptake and histologic grade of neuroendocrine tumors. (68)Ga-DOTATATE imaging changed management in 36 patients (70.6%), who were subsequently deemed suitable for peptide receptor-targeted therapy.. In patients with negative or equivocal (111)In-DTPA-octreotide findings, (68)Ga-DOTATATE PET identifies additional lesions and may alter management in most cases.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Biological Transport; Humans; Male; Middle Aged; Neuroendocrine Tumors; Octreotide; Organometallic Compounds; Pentetic Acid; Positron-Emission Tomography; Receptors, Somatostatin; Retrospective Studies; Tomography, X-Ray Computed; Young Adult

We aimed to evaluate (68)Ga-DOTATATE PET/CT for the early prediction of time to progression and clinical outcome after a first cycle of peptide receptor radionuclide treatment (PRRT) in a cohort of patients with well-differentiated neuroendocrine tumors.. Thirty-three consecutive patients (22 men and 11 women; mean age +/- SD, 57.8 +/- 12.1 y) were investigated at baseline and again 3 mo after initiation of the first cycle of PRRT. (68)Ga-DOTATATE receptor expression was assessed using 2 measures of standardized uptake value (SUV): maximum SUV (SUV(max)) and tumor-to-spleen SUV ratio (SUV(T/S)). Percentage change in SUV scores after PRRT relative to baseline (DeltaSUV) was calculated. After completing 1-3 cycles of PRRT, patients entered the follow-up study, for estimation of time to progression. According to the Response Evaluation Criteria in Solid Tumors, progression was defined on the basis of contrast-enhanced CT. Clinical symptoms, as well as the tumor markers chromogranin A and neuron-specific enolase, were also recorded during regular follow-up visits.. The 23 of 31 patients with decreased SUV(T/S) after the first PRRT cycle had longer progression-free survival than did the 8 of 31 patients with stable or increased scores (median survival not reached vs. 6 mo, P = 0.002). For the 18 of 33 patients showing a reduction in SUV(max), there was no significant difference in progression-free survival (median survival not reached vs. 14 mo, P = 0.22). Multivariate regression analysis identified SUV(T/S) as the only independent predictor for tumor progression during follow-up. In the 17 of 33 patients with clinical symptoms before PRRT, DeltaSUV(T/S) correlated with clinical improvement (r = 0.52, P < 0.05), whereas DeltaSUV(max) did not (r = 0.42, P = 0.10). Changes in the tumor markers (chromogranin A and neuron-specific enolase) did not predict DeltaSUV scores, clinical improvement, or time to progression.. Decreased (68)Ga-DOTATATE uptake in tumors after the first cycle of PRRT predicted time to progression and correlated with an improvement in clinical symptoms among patients with well-differentiated neuroendocrine tumors; DeltaSUV(T/S) was superior to DeltaSUV(max) for prediction of outcome.

Topics: Adult; Aged; Biomarkers, Tumor; Cell Differentiation; Disease Progression; Disease-Free Survival; Female; Humans; Male; Middle Aged; Neuroendocrine Tumors; Organometallic Compounds; Positron-Emission Tomography; Receptors, Somatostatin; Time Factors; Tomography, X-Ray Computed; Treatment Outcome; Young Adult

We report a 74-year-old male with liver metastases from a neuroendocrine tumor (NET) of unknown origin. Conventional imaging studies with ultrasound, computed tomography colonoscopy and Positron emission tomography-computed tomography (PET/CT) with 18Fluor odeoxyglucose did not identify the site of origin of the primary tumor. The patient was submitted for a PET/CT scan with a new radiopharmaceuticai, the somatostatin analogue 68Ga-DOTATATE. This new technique demonstrated increased focal uptake at the ileocecal valve. This lesion and other two liver metastases were surgically removed. The histopathology and immunohistochemistry analysis confirmed the diagnosis of NET (carcinoid). This case illustrates the advantages of the PET/CT scan with 68Ga-DOTATATE.

Topics: Aged; Humans; Ileal Neoplasms; Ileocecal Valve; Liver Neoplasms; Male; Neuroendocrine Tumors; Organometallic Compounds; Positron-Emission Tomography; Tomography, X-Ray Computed

(68)Ga-labeled 1,4,7,10-tetraazacyclododecane-N,N',N'',N'''-tetraacetic acid-d-Phe(1)-Tyr(3)-octreotide (DOTA-TOC) PET has proven its usefulness in the diagnosis of patients with neuroendocrine tumors. Radionuclide therapy ((90)Y-DOTA-TOC or (177)Lu-DOTA-octreotate) is a choice of treatment that also requires an accurate diagnostic modality for early evaluation of treatment response. Our study compared (68)Ga-DOTA-TOC PET with CT or MRI using the Response Evaluation Criteria in Solid Tumors. Furthermore, standardized uptake values (SUVs) were calculated and compared with treatment outcome.. Forty-six patients (29 men, 17 women; age range, 34-84 y) with advanced neuroendocrine tumors were investigated before and after 2-7 cycles of radionuclide therapy. Long-acting somatostatin analogs were not applied for at least 6 wk preceding the follow-up. Data were acquired with a dedicated PET scanner. Emission image sets were acquired at 90-100 min after injection. (68)Ga-DOTA-TOC PET images were visually interpreted by 2 experienced nuclear medicine physicians. For comparison, multislice helical CT scans and 1.5-T MRI scans were obtained. Attenuation-corrected PET images were used to determine SUVs. Repeated CT evaluation and other imaging modalities, for example, (18)F-FDG, were used as the reference standard.. According to the reference standard, (68)Ga-DOTA-TOC PET and CT showed a concordant result in 32 patients (70%). In the remaining 14 patients (30%), discrepancies were observed, with a final outcome of progressive disease in 9 patients and remission in 5 patients. (68)Ga-DOTA-TOC PET was correct in 10 patients (21.7%), including 5 patients with progressive disease. In these patients, metastatic spread was detected with the follow-up whole-body PET but was missed when concomitant CT was used. On the other hand, CT confirmed small pulmonary metastases not detected on (68)Ga-DOTA-TOC in 1 patient and progressive liver disease not detected on (68)Ga-DOTA-TOC in 3 patients. Quantitative SUV analysis of individual tumor lesions showed a large range of variability.. (68)Ga-DOTA-TOC PET shows no advantage over conventional anatomic imaging for assessing response to therapy when all CT information obtained during follow-up is compared. Only the development of new metastases during therapy was detected earlier in some cases when whole-body PET was used. SUV analysis of individual lesions is of no additional value in predicting individual responses to therapy.

Topics: Adult; Aged; Aged, 80 and over; Female; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Neuroendocrine Tumors; Octreotide; Organometallic Compounds; Positron-Emission Tomography; Prognosis; Radiopharmaceuticals; Receptors, Somatostatin; Reproducibility of Results; Sensitivity and Specificity; Tomography, X-Ray Computed; Treatment Outcome

Our purpose was to compare the performance of (68)Ga-1,4,7,10-tetraazacyclododecane-N,N',N'',N'''-tetraacetic acid-d-Phe(1),Tyr(3)-octreotate (DOTATATE), a novel selective somatostatin receptor 2 PET ligand, and (18)F-FDG in the detection of pulmonary neuroendocrine tumors using PET/CT, with correlation of uptake and tumor grade on histology.. The imaging findings of the first 18 consecutive patients (8 men and 10 women) with pulmonary neuroendocrine tumors (11 typical carcinoids, 2 atypical carcinoids, 1 large cell neuroendocrine tumor, 1 small cell neuroendocrine carcinoma, 1 non-small cell lung cancer with neuroendocrine differentiation, and 2 cases of diffuse idiopathic pulmonary neuroendocrine cell hyperplasia) who underwent (68)Ga-DOTATATE and (18)F-FDG PET/CT were reviewed. In all cases, the diagnosis was established on histology.. Of 18 patients, 15 had primary tumors (median size, 2.7 cm; range, 0.5-8 cm) and 3 had recurrent tumors. All typical carcinoids showed high uptake of (68)Ga-DOTATATE (maximum standardized uptake value [SUV(max)] >or= 8.2), but 4 of 11 showed negative or minimal (18)F-FDG uptake (SUV(max) = 1.7-2.9). All tumors of higher grade showed high uptake of (18)F-FDG (SUV(max) >or= 11.7), but 3 of 5 showed only minimal accumulation of (68)Ga-DOTATATE (SUV(max) = 2.2-2.8). Neither case of diffuse idiopathic pulmonary neuroendocrine cell hyperplasia showed uptake of (68)Ga-DOTATATE or (18)F-FDG. Typical carcinoids showed significantly higher uptake of (68)Ga-DOTATATE and significantly less uptake of (18)F-FDG than did tumors of higher grade (P = 0.002 and 0.005). There was no instance of false-positive uptake of (68)Ga-DOTATATE, but there were 3 sites of (18)F-FDG uptake secondary to inflammation. (68)Ga-DOTATATE was superior to (18)F-FDG in discriminating endobronchial tumor from distal collapsed lung (P = 0.02).. Typical bronchial carcinoids showed higher and more selective uptake of (68)Ga-DOTATATE than of (18)F-FDG. Atypical carcinoids and higher grades had less (68)Ga-DOTATATE avidity but were (18)F-FDG-avid.

Topics: Adult; Aged; Aged, 80 and over; Biological Transport; Female; Fluorodeoxyglucose F18; Humans; Lung Neoplasms; Male; Middle Aged; Neuroendocrine Tumors; Organometallic Compounds; Positron-Emission Tomography; Receptors, Somatostatin; Retrospective Studies; Tomography, X-Ray Computed

The aim was to assess the relevant distribution of the novel PET tracer (68)Ga-DOTATATE in neuroendocrine tumors (NETs) with combined positron emission tomography / computed tomography (PET/CT) and compare its performance with that of (18)F-FDG PET/CT.. The imaging findings with (68)Ga-DOTATATE and (18)F-FDG on 38 consecutive patients with a diagnosis of primary or recurrent NET were compared and correlated with tumor grade on histology based on ki67 and mitotic index.. The sensitivity of (68)Ga-DOTATATE PET/CT was 82% (31 of 38) and that of (18)F-FDG PET/CT was 66% (25 of 38). The sensitivity of combined (68)Ga-DOTATATE and (18)F-FDG PET/CT was 92% (35 of 38). There was greater uptake of (68)Ga-DOTATATE than (18)F-FDG in low-grade NET (median SUV 29 vs 2.9, P < .001). In high-grade NET there was higher uptake of (18)F-FDG over (68)Ga-DOTATATE (median SUV 11.7 vs 4.4, P = .03). There was a significant correlation with predominant tumor uptake of (68)Ga-DOTATATE or (18)F-FDG and tumor grade on histology (P < .0001).. (68)Ga-DOTATATE PET/CT is a useful novel imaging modality for NETs and is superior to (18)F-FDG for imaging well-differentiated NET. Functional imaging with both (68)Ga-DOTATATE and (18)F-FDG has potential for a more comprehensive tumor assessment in intermediate- and high-grade tumors.

Topics: Adolescent; Adult; Aged; Female; Fluorodeoxyglucose F18; Gallium; Humans; Male; Middle Aged; Neuroendocrine Tumors; Organometallic Compounds; Positron-Emission Tomography; Prognosis; Radiopharmaceuticals; Retrospective Studies; Survival Rate; Tomography, X-Ray Computed

Topics: Dihydroxyphenylalanine; Humans; Neuroendocrine Tumors; Organometallic Compounds; Positron-Emission Tomography; Radiopharmaceuticals; Sensitivity and Specificity