n-n-dimethyl-n-(18f)fluoromethyl-2-hydroxyethylammonium and fluorocholine

Minimally invasive parathyroidectomy (MIP) is the standard of care for primary hyperparathyroidism (PHPT). Four dimensional computed tomography(4DCT) and F-18 Fluorocholine positron emission tomography/computed tomography (FCH PET/CT) localize adenomas accurately to perform MIP. We aimed to conduct a systematic review and metanalysis to evaluate the diagnostic performance of 4DCT and FCH PET/CT scan for quadrant wise localisation in PHPT patients and to do head-to-head comparison between these two modalities. DESIGN, PATIENTS AND MEASUREMENT : After searching through PubMed and EMBASE databases, 46 studies (using histology as a gold standard) of 4DCT and FCH PET/CT were included. RESULTS: Total number of patients included were 1651 and 952 for 4DCT scan (studies n = 26) and FCH PET/CT scan (studies n = 24) respectively. In per patient analysis, FCH PET/CT and 4DCT had pooled sensitivities of 92% (88-94) and 85% (73-92) respectively and in per lesion analysis, 90% (86-93) and 79% (71-84), respectively. In the subgroup with negative conventional imaging/persistent PHPT, FCH PET/CT had comparable sensitivity to 4DCT (84% [74-90] vs. 72% [46-88]). As per patient wise analysis, FCH PET/CT had better detection rates than 4DCT ([92.4 vs. 76.85], odds ratio -3.89 [1.6-9.36] p = .0024) in the subpopulation where both FCH PET/CT and 4DCT were reported. CONCLUSION: Both 4DCT and FCH PET/CT scan performed well in newly diagnosed patients, patients with persistent disease and in those with inconclusive conventional imaging results. FCH PET/CT scan had a higher pooled sensitivity than 4DCT in detecting patients with PHPT in head to head comparison.

Topics: Choline; Four-Dimensional Computed Tomography; Humans; Hyperparathyroidism, Primary; Parathyroid Glands; Positron Emission Tomography Computed Tomography

Primary hyperparathyroidism (pHPT) is a common endocrine disorder caused by an autonomous overproduction of parathyroid hormone (PTH) by a parathyroid gland. Over the last decade,. We conducted a systematic review and metaanalysis according to the PRISMA Guidelines. A literature search was performed in the PubMed, Web of Science and Cochrane databases, last updated November 2022. Original articles on choline PET in patients with pHPT mentioning patient-based sensitivity, PPV and cure rate were retained. Quality of included studies was assessed using the QUADAS-2 Tool. Patient-based sensitivity, PPV and cure rate were pooled by using a random-effects model.. Twenty-three studies including 1716 patients were included for quantitative assessment. FCH PET showed a pooled patient-based sensitivity of 93.8% (95% CI: 89.8-96.3) and PPV of 97% (95% CI: 92.8-98.8) in patients with pHPT. Parathyroid surgery was performed in 1129 patients. The pooled cure rate of PET-guided surgery was 92.8% (95% CI: 87.4-96.0). Heterogeneity was shown to be moderate for all effect sizes.. FCH PET showed a high patient-based sensitivity, PPV and cure rate of PET guided surgery in patients with pHPT.

Topics: Choline; Humans; Hyperparathyroidism, Primary; Parathyroid Glands; Positron Emission Tomography Computed Tomography; Positron-Emission Tomography

Localized very high-risk prostate cancer (VHR PCa) has long suffered from the inex-istence of good lymph node staging methods other than invasive surgery, as computed tomogra-phy has low sensitivity for nodal disease. With the rising use of positron emission tomography (PET), it is clinically meaningful to know its value for these patients. Our goal was to evaluate the real-life diagnostic accuracy of PET Choline in nodal staging, comparing it with the gold standard of extended pelvic lymph node dissection (ePLND).. We reviewed data from a high-volume center, including patients with VHR PCa according to current NCCN guidelines who underwent community 18F-fluorocholine PET/CT; followed by ro-botic assisted laparoscopic prostatectomy (RALP) and ePLND between 2010 and 2021.. We included 44 patients and 88 lymph node regions. Among those, 14/44 (31.8%) patients and 20/88 (22.7%) regions had nodal disease present on definitive pathology. In comparison with ePLND, we found a sensitivity of 64.3% (95% CI, 39.2-89.4%), specificity of 83.3% (95% CI, 70.0- 96.7%), PPV of 64.3% (95% CI, 39.2-89.4%), and NPV of 83.3% (95% CI, 70.0-96.7%) for nodal disease on a patient-based analysis; and sensitivity of 35.0% (95% CI, 14.1-60.0%), specificity of 88.2% (95% CI, 80.6-95.9%), PPV of 46.7% (95% CI, 21.4-71.9%), and NPV of 82.2% (95% CI, 73.4-91.0%) on a region-based analysis.. In our view 18F-fluorocholine PET/CT doesn't meet the criteria to be a standard exam for pre-operative staging for patients with VHR PCa, mostly due to its low sensitivity. However, other radiotracers should continue to be investigated in this setting.

Topics: Choline; Humans; Lymph Node Excision; Lymph Nodes; Lymphatic Metastasis; Male; Neoplasm Staging; Positron Emission Tomography Computed Tomography; Positron-Emission Tomography; Prostatic Neoplasms; Tomography, X-Ray Computed

The bombesin derivative RM2 is a GRPr antagonist with strong binding affinity to prostate cancer (PCa). In this study, the impact of [. This phase I/II study was conducted in 30 biopsy-positive PCa subjects. The patients were stratified into high (10 patients), intermediate (10 patients), and low risk (10 patients) for extraglandular metastases as defined by National Comprehensive Cancer Network (NCCN) criteria (NCCN Clinical Practice Guidelines in Oncology, 2016). The prostate gland was classified in 12 anatomic segments for data analysis of the imaging modalities as well as histopathologic findings. The segment with the highest radiotracer uptake was defined as the "index lesion." All cases were scheduled to undergo prostatectomy with pelvic lymph node (LN) dissection in intermediate- and high-risk patients. Intraprostatic and pelvic nodal [. [

Topics: Bombesin; Choline; Gallium Radioisotopes; Humans; Male; Multiparametric Magnetic Resonance Imaging; Positron Emission Tomography Computed Tomography; Prostatic Neoplasms

This prospective, multicenter, open-label, randomized, crossover trial study was to evaluate the diagnostic performance of 18F-PSMA-1007 (PSMA) vs. 18F-Choline PET/CT (FCH) in prostate cancer (PCa) patients (pts) with biochemical recurrence (BCR).. One hundred eighty-six pts, who have undergone primary definitive treatment for PCa with BCR, were recruited to this prospective study. All pts underwent one PSMA and one FCH PET/CT examination in randomized order within a time frame of 8 days and were followed up for at least 6 months (182 ± 10 days).. Recurrence of PCa was observed in 176 out of 186 pts. The overall correct detection rate (DR) was 84% (95% CI 0.7967-0.8830) for PSMA and 69% (95% CI 0.6191-0.7489) for FCH, yielding a difference in proportion of 16% ( P  < 0.0001). PSMA had a sensitivity of 0.8464 and FCH 0.6857 with an odds ratio of 2.5259 ( P  < 0.0001), with statistically significant greater sensitivity of PSMA (ORs, 2.7877 and 2.1283 respectively) ( P  < 0.0001). PET/CT imaging led to a more accurate diagnosis in 166 (89.2%) pts, of which PSMA had contributed more than FCH in 91 (54.8%) of them. The DR for cutoff point PSA ≤ 1 ng/ml was higher for PSMA compared to FCH (61.8% vs. 39.5%). DR value of 51.6% for PSMA reached at PSA ≤ 0.3 ng/ml, while FCH reached that DR value with PSA ≤ 2.2 ng/ml.. 18F-PSMA-1007 is more efficacious than 18F-Choline for the identification metastatic lesions both in patient and in regional level analysis in PCa patients with BCR.

Topics: Choline; Gallium Radioisotopes; Humans; Male; Neoplasm Recurrence, Local; Positron Emission Tomography Computed Tomography; Prospective Studies; Prostate-Specific Antigen; Prostatic Neoplasms

The role of positron emission tomography/computed tomography (PET/CT) in hepatocellular carcinoma (HCC) management is not clearly defined. Our objective was to analyze the utility of dual-PET/CT (. Between January 2011 and April 2019, 168 consecutive HCC patients with available baseline dual-PET/CT imaging data were retrospectively analyzed. To identify potential refinement criteria for surgically-treated patients, survival Kaplan-Meier curves of various standard-of-care and dual-PET/CT baseline parameters were estimated. Finally, multivariate cox proportional hazard ratios of the most relevant clinico-biological and/or PET parameters were estimated.

Topics: alpha-Fetoproteins; Carcinoma, Hepatocellular; Choline; Fluorodeoxyglucose F18; Humans; Liver Neoplasms; Positron Emission Tomography Computed Tomography; Positron-Emission Tomography; Prospective Studies; Radiopharmaceuticals; Retrospective Studies

The aim of this study is to determine accurately the localization of the adenoma with the imaging methods in the patients, who are planned to be operated on with prediagnosis of parathyroid adenoma.. In our study, the files of the patients who were considered to have parathyroid adenoma and underwent operation between 2012 and 2020 with the methods such as Tc99m-MIBI SPECT/CT, 18F-fluorocholine PET/CT, and ultrasound, and biochemical examinations were examined retrospectively.. In this study, 31 (18.2%) male and 139 (81.8%) female adult patients were included. The sensitivities of localization methods were 82.6% for ultrasound and 78.4% for scintigraphy. Adenoma was localised in the right place in 14 of 15 (93.3%) patients with the 18F-fluorocholine PET/CT method. A statistically significant correlation was found between the sensitivity of scintigraphy, the gland weights (p: 0.002), and phosphor values (p: 0.039). A statistically significant improvement was observed in the intact PTH value (p: 0.001) 15 min after the removal of adenoma. A statistically significant improvement was observed in the serum PTH value (p: 0.001), the serum phosphorus value (p: 0.001), and the serum calcium (p: 0.001) in the first 3 months after the operation.. Determining localization accurately for the patients enables performing operations with minimally invasive surgery successfully in a shorter time. Also, fewer complications and faster recovery are seen in the patients. It was concluded that studying intraoperative intact PTH and using 18F-fluorocholine PET/CT method for localization give more accurate results for localization and allow having more successful operation outcomes.

Topics: Adenoma; Adult; Female; Humans; Hyperparathyroidism, Primary; Male; Parathyroid Glands; Parathyroid Neoplasms; Positron Emission Tomography Computed Tomography; Retrospective Studies; Technetium Tc 99m Sestamibi; Tomography, Emission-Computed, Single-Photon

Forty patients with suspect primary hyperparathyroidism (pHPT) and negative/equivocal conventional imaging underwent FCH-PET/CT in our Institution. For every lesion, visual and semi-quantitative analyses were performed on PET/CT images. In qualitative analysis, a lesion was considered positive if a clear focus of uptake, significantly higher than normal thyroid tissue, was identifiable. Ectopic focal uptake was also regarded as positive PET result. Lesion SUV. Four out of the 40 patients who underwent surgery for pHPT had more than one histologic proven unhealthy parathyroid and three had papillary thyroid cancer (PTC). A total of 48 lesions were analyzed. We found 42/48 lesions (87.5%) to have true-positive uptake, whereas three lesions (6.7%) had false-positive uptake (PTC). Three histologic proven parathyroid adenomas showed no uptake (6.7%); the sensitivity/PPV were 93.3% and accuracy was 87,8%. Pearson's test showed a significant correlation between PTH values and parathyroid size with SUVr values (r = 0.56 and 0.55, respectively, p < 0.01 for both features).. As stated in recent literature, we observed excellent diagnostic sensitivity of FCH-PET/CT in patients with pHPT, providing surgeons a fine tool to optimize treatment. More studies are needed to improve the evaluability of semi-quantitative parameters towards a further improvement of diagnostic accuracy.

Topics: Choline; Humans; Hyperparathyroidism, Primary; Parathyroid Glands; Positron Emission Tomography Computed Tomography; Retrospective Studies

In a 54-year-old patient referred for 18F-fluorocholine (FCH) baseline PET/CT before chemotherapy for biopsy-proven liver metastases, FCH PET/CT demonstrated multiple hypodense hepatic lesions with no FCH uptake and 2 positive bone metastases. FCH PET/CT performed after 6 cycles of docetaxel demonstrated a near normalization of the physiological uptake in the area of the sterilized liver metastases, which was confirmed by a drop in prostate-specific antigen and a complete metabolic response in the bone metastases. The present case demonstrates a new pattern of response defined by a reverse phenomenon from photopenic to normal uptake in responding liver metastases.

Topics: Bone Neoplasms; Choline; Humans; Liver Neoplasms; Male; Middle Aged; Positron Emission Tomography Computed Tomography; Prostatic Neoplasms

Few clinical and preclinical articles reported the potential usefulness of 18F-choline PET/CT in several hematological proliferative diseases. We report and incidental finding of a superscan-like pattern in a patient affected by essential thrombocythemia (ET), performing 18F-choline PET/CT for a biochemical recurrence of prostate cancer. The mild elevation of PSA values and the negativity of subsequent 68Ga-PSMA-11 PET/CT allowed to correlate the diffuse skeletal uptake detected on 18F-choline PET/CT to the underlying hematologic disease, rather than to a prostate cancer relapse.

Topics: Choline; Humans; Male; Neoplasm Recurrence, Local; Positron Emission Tomography Computed Tomography; Positron-Emission Tomography; Prostate-Specific Antigen; Prostatic Neoplasms; Thrombocythemia, Essential; Tomography, X-Ray Computed

We describe a case of a 56-year-old woman with primary hyperparathyroidism. 18F-Choline PET/MRI revealed incidental bilateral axillary lymphadenopathy with mild-moderate increased 18F-choline uptake. The patient had her first and third doses of COVID-19 vaccines from the left arm and second dose of vaccine from the right arm before PET examination.

Topics: Choline; COVID-19; COVID-19 Vaccines; Female; Humans; Hyperparathyroidism; Lymphadenopathy; Magnetic Resonance Imaging; Middle Aged; Positron Emission Tomography Computed Tomography; Positron-Emission Tomography; Radiopharmaceuticals; Vaccines

The contribution of [18F]F-fluorocholine (FCH)-positron emission tomography (PET)/computed tomography (CT) in normocalcemic primary hyperparathyroidism (nPHPT) remains unknown.. To evaluate the sensitivity and specificity of FCH-PET/CT in a cohort of osteoporotic patients with nPHPT and discordant or negative [99mTc]Tc-sestamibi scintigraphy and ultrasonography who all underwent parathyroidectomy (PTX).. Longitudinal retrospective cohort study in patients referred for osteoporosis with mild biological primary hyperparathyroidism.. Tertiary referral center with expertise in bone metabolism and surgical management of hyperparathyroidism.. Among 109 patients with PHPT analyzed, 3 groups were individualized according to total serum calcium (tCa) and ionized calcium (iCa): 32 patients with hypercalcemia (HtCa group), 39 patients with normal tCa and elevated iCa (NtCa group), and 38 patients with both normal tCa and iCa (NiCa). All patients had biochemical follow-up confirming or not the success of PTX.. To evaluate the performance of FCH-PET/CT in terms of sensitivity and specificity, and to compare with first-line imaging procedures in the setting of nPHPT.. The sensitivity of FCH-PET/CT was 67% in the hypercalcemic group, 48% in the NtCa group (P = .05 vs HtCa), and 33% in the NiCa group (P = .004 vs HtCa). Specificity ranged from 97% to 99%. FCH-PET/CT was positive in 64.3% of patients with negative conventional imaging, with biochemical resolution after PTX in 77.8% of patients. Triple negative imaging was observed in 20 patients, with PHPT resolution in 85% of these patients.. This study highlights the contribution of FCH-PET/CT in a well-phenotyped cohort of normocalcemic patients with discordant or negative findings in [99mTc]Tc-sestamibi scintigraphy and ultrasonography. However, negative imaging in nPHPT does not rule out the possibility of surgical cure by an experienced surgeon.

Topics: Calcium; Choline; Humans; Hyperparathyroidism, Primary; Organotechnetium Compounds; Parathyroid Glands; Positron Emission Tomography Computed Tomography; Radionuclide Imaging; Radiopharmaceuticals; Retrospective Studies; Technetium Tc 99m Sestamibi; Ultrasonography

The median baseline prostate-specific antigen was 11 ng/mL, the Gleason score was > 7 for 54% of patients, and the clinical stage was T1/T2 for 89% and T3 for 9% of patients. The baseline clinical model achieved an area under the receiver operating characteristic curve (AUC) of 0.73. Performances improved when clinical data were combined with radiomic features, in particular for PG. Radiomics reinforces clinical parameters in predicting BCR in intermediate and high-risk PCa patients. These first data strongly encourage further investigations on the use of radiomic analysis to identify patients at risk of BCR.

Topics: Artificial Intelligence; Humans; Male; Positron Emission Tomography Computed Tomography; Prostate-Specific Antigen; Prostatic Neoplasms; Retrospective Studies

We present the case of a 68-year-old woman with a painful tibial tumor and fatigue. Histology and laboratory studies were consistent with a brown tumor secondary to initially unrecognized, severe primary hyperparathyroidism. 18 F-fluorocholine PET/CT revealed a large hypermetabolic parathyroid mass and multiple bone foci considered as brown tumors. Unilateral neck exploration confirmed a large parathyroid adenoma. Serum calcium and parathyroid hormone levels normalized quickly, and symptoms subsided gradually after parathyroidectomy. Brown tumors are a rare complication of severe hyperparathyroidism. 18 F-fluorocholine PET/CT allows the localization of parathyroid adenomas and brown tumors, and can be used as a single imaging modality.

Topics: Aged; Choline; Female; Humans; Hyperparathyroidism, Primary; Osteitis Fibrosa Cystica; Parathyroid Glands; Parathyroid Neoplasms; Positron Emission Tomography Computed Tomography

To assess the diagnostic and therapeutic impact of PET/CT with 18F-DCFPyL with respect to 18F-Fluorocholine in initial staging of intermediate-/high-risk prostate cancer (PCa).. Patients with recent diagnosis of intermediate-/high-risk PCa without androgen deprivation therapy and previous 18F-Fluorocholine-PET/CT (negative for extraprostatic disease or with oligometastatic disease) were referred to 18F-DCFPyL-PET/CT. Patients' disease characteristic as grade group, D'Amico risk category (intermediate/high), prostate-specific antigen (PSA) closest to PET/CTs and its kinetics were obtained. The overall detection rate (DR) and molecular imaging TNM (miTNM) stage according to the prostate cancer molecular imaging standardized evaluation (PROMISE) criteria were assessed for both radiotracers, and their concordance (Kappa coefficient) was analyzed. The diagnostic and therapeutic impact of 18F-DCFPyL with respect to 18F-Fluorocholine was evaluated.. Fifty-eight patients were analyzed (84.5% high-risk). 18F-Fluorocholine showed a higher DR than 18F-DCFPyL of prostate gland involvement (100% versus 93.1%) and pelvic node disease (37.9% versus 31%; k = 0.436, p = 0.001). On the other hand, 18F-DCFPyL-PET/CT showed a higher DR of metastatic disease than 18F-Fluorocholine-PET/CT, 9/58 patients (15.5%): 3 M1a, 5 M1b and 1 M1c) versus 5/58 (8.6%) patients: 1 M1a and 4 M1b), k = 0.426; p = 0.001. No significant association was found between clinical characteristics (grade group, risk category, PSA level and kinetic) and 18F-Fluorocholine or 18F-DCFPyL results. The results of 18F-DCFPyL-PET/CT modified the previously planned treatment compared to 18F-Fluorocholine-PET/CT in 13 patients (22.4%).. 18F-Fluorocholine and 18F-DCFPyL PET/CT showed a similar DR of prostate gland and lymph node involvement, although with moderate concordance for the latter. 18F-DCFPyL was superior to 18F-Fluorocholine in detecting regional and distant metastasis with a therapeutic impact in one of every five patients.

Topics: Androgen Antagonists; Humans; Male; Pilot Projects; Positron Emission Tomography Computed Tomography; Prostate-Specific Antigen; Prostatic Neoplasms

A 54-year-old woman diagnosed with multiple endocrine neoplasia syndrome type 1 and primary hyperparathyroidism underwent total parathyroidectomy with autotransplantation of parathyroid tissue fragments in the right forearm in 1999. Since several years later, follow-up laboratory examinations showed the relapse of hypercalcemia; the patient started cinacalcet therapy. To exclude the presence of hyperfunctioning parathyroid glands in ortotopic or ectopic sites, a PET/CT scan with 18F-fluorocholine was performed. The PET/CT scan excluded the presence of ortotopic and ectopic parathyroid glands but showed a hyperplastic parathyroid fragment in the right forearm, responsible for the patient's persistent hypercalcemia.

Topics: Choline; Female; Humans; Hypercalcemia; Hyperparathyroidism, Primary; Middle Aged; Neoplasm Recurrence, Local; Parathyroid Glands; Positron Emission Tomography Computed Tomography

We aimed to evaluate the power of 18F-fluorocholine (FCH) positron emission tomography/magnetic resonance (PET/MR) imaging in unlocalized primary hyperparathyroidism.. Thirty-four patients were included. In 17/34 patients, PET/MR was performed immediately after a negative 18F-FCH PET/CT. Sensitivity, specificity, positive and negative predictive values were calculated for MR only (blinded to PET data) and PET only (blinded to MR data) findings.. 18F-FCH PET/MR was positive in 26/34 (76%) patients. PET/MR was also positive in 12/17 (71%) patients with a negative PET/CT. Among 11/34 (32%) patients where 18F-FCH PET-only and MR-only results were discordant, MR was false positive in 7/11 patients (3/7 of the lesions were not 18F-FCH avid and in 4/7 of them PET and MRI pointed different locations. Postoperative histopathology revealed that 18F-FCH-positive ones were true positives). Sensitivity, specificity, PPV, NPV and accuracy of neck MR evaluated blinded to PET data were 80%, 50%, 70%, 64% and 68%, respectively, and all were calculated as 100% for PET/MR.. 18F-FCH PET/MR is very effective in preoperative localization of parathyroid adenomas even if 18F-FCH PET/CT is negative. Neck MR alone is insufficient in detecting parathyroid adenomas but PET/MR combination helps in precise localisation.

Topics: Choline; Humans; Hyperparathyroidism, Primary; Magnetic Resonance Imaging; Magnetic Resonance Spectroscopy; Parathyroid Neoplasms; Positron Emission Tomography Computed Tomography; Positron-Emission Tomography

A 79-year-old man with a history of prostate adenocarcinoma treated with prostatectomy underwent 18F-FCH PET/CT for restaging purpose, which was negative for relapse but showed the presence of choline-positive lymph nodes in the left axilla. The patient underwent a COVID-19 vaccination in the left arm 6 days prior. Thus, PET/CT findings were considered as inflammatory lymph nodes. With the current drive of global COVID-19 immunization, this case underlines the importance of knowing vaccination history to interpret correctly the findings and to avoid false-positive reports.

Topics: Aged; Choline; COVID-19; COVID-19 Vaccines; Humans; Lymphadenopathy; Male; Neoplasm Recurrence, Local; Positron Emission Tomography Computed Tomography; Positron-Emission Tomography; Prostate-Specific Antigen; Prostatectomy; Prostatic Neoplasms; SARS-CoV-2; Vaccination

Positron emission tomography-computed tomography (PET-CT) with [. The study retrospectively examined 177 patients with intermediate or high-risk prostate cancer who had undergone staging with FCH PET-CT before ePLND. Images were obtained with either the conventional Philips Gemini PET-CT (n = 93) or the digital SiPM-based GE Discovery MI PET-CT (n = 84) and compared.. Images that were obtained using the Philips Gemini PET-CT system showed 19 patients (20%) with suspected lymph node metastases, whereas the GE Discovery MI PET-CT revealed 36 such patients (43%). The sensitivity, specificity, and positive and negative predictive values were 0.3, 0.84, 0.47, and 0.72 for the Philips Gemini, while they were 0.58, 0.62, 0.31, and 0.83 for the GE Discovery MI, respectively. The areas under the curves in a receiver operating characteristic curve analysis were similar between the two PET-CT systems (0.57 for Philips Gemini and 0.58 for GE Discovery MI, p = 0.89).. Marked differences in sensitivity and specificity were found for the different PET-CT systems, although the overall diagnostic performance was similar. These differences are probably due to differences in both hardware and software, including reconstruction algorithms, and should be considered when new technology is introduced.

Topics: Choline; Humans; Lymph Nodes; Lymphatic Metastasis; Male; Neoplasm Staging; Positron Emission Tomography Computed Tomography; Prostatic Neoplasms; Radiopharmaceuticals; Retrospective Studies

We used a dataset of 93 subjects with PHPT imaged using FCH-PET, of which 74 subjects had visible HPTT while 19 controls had no visible HPTT on FCH-PET. A conventional Resnet10 as well as a novel mPETResnet10 DL model were trained and tested to detect (present, not present) and localise (upper left, lower left, upper right or lower right) HPTT. Our mPETResnet10 architecture also contained a region-of-interest masking algorithm that we evaluated qualitatively in order to try to explain the model's decision process.. The models detected the presence of HPTT with an accuracy of 83% and determined the quadrant of HPTT with an accuracy of 74%. The DL methods performed statistically worse (p < 0.001) in both tasks compared to human readers, who localise HPTT with the accuracy of 97.7%. The produced region-of-interest mask, while not showing a consistent added value in the qualitative evaluation of model's decision process, had correctly identified the foreground PET signal.. Our experiment is the first reported use of DL analysis of FCH-PET in PHPT. We have shown that it is possible to utilize DL methods with FCH-PET to detect and localize HPTT. Given our small dataset of 93 subjects, results are nevertheless promising for further research.

Topics: Deep Learning; Humans; Parathyroid Glands; Positron Emission Tomography Computed Tomography

To investigate the diagnostic accuracy of O-(2-[18F]-fluoroethyl)-L-tyrosine (18F-FET) and fluoromethyl-(18F)-dimethyl-2-hydroxyethyl-ammonium chloride (18F-FCH) computed tomography (CT) in patients with primary low-grade gliomas (LGG).. The study enrolled patients with magnetic resonance imaging (MRI)-suspected LGG. Patients underwent both 18F-FET and 18F-FCH positron emission tomography (PET)-CT. Brain PET-CT was performed according to standard protocol - 20 minutes after intravenous injection of 185 MBq of 18F-FET and 185 MBq of 18F-FCH PET. Surgery and pathohistological diagnosis were performed in the next two weeks.. We observed significantly better concordance between tumor histology and 18F-FET PET (weighted Kappa 0.74) compared with both 18F-FCH (weighted Kappa 0.15) and MRI (weighted Kappa 0.00). Tumor histology was significantly associated with 18F-FET (odds ratio 12.87; 95% confidence interval [CI], 0.49-333.70; P=0.013, logistic regression analysis). Receiver operating characteristic curve analysis comparing 18F-FCH (area under the curve [AUC] 0.625, 95% CI 0.298-0.884) and 18F-FET (AUC 0.833, 95% CI 0.499-0.982) showed better diagnostic properties of 18F-FET (AUC difference 0.208, 95% CI -0.145 to 0.562, P=0.248).. Performing PET-CT in patients with newly diagnosed LGG should be preceded by a selection of an appropriate radiopharmaceutical. 18F-FET seems to be more accurate than 18F-FCH in the LGG diagnosis.

Topics: Brain Neoplasms; Choline; Glioma; Humans; Magnetic Resonance Imaging; Pilot Projects; Positron Emission Tomography Computed Tomography; Positron-Emission Tomography; Radiopharmaceuticals; Tyrosine

Choline kinase is upregulated in prostate cancer, resulting in increased (18)F-fluoromethylcholine uptake. This study used pharmacokinetic modeling to validate the use of simplified methods for quantification of (18)F-fluoromethylcholine uptake in a routine clinical setting.. Forty-minute dynamic PET/CT scans were acquired after injection of 204 ± 9 MBq of (18)F-fluoromethylcholine, from 8 patients with histologically proven metastasized prostate cancer. Plasma input functions were obtained using continuous arterial blood-sampling as well as using image-derived methods. Manual arterial blood samples were used for calibration and correction for plasma-to-blood ratio and metabolites. Time-activity curves were derived from volumes of interest in all visually detectable lymph node metastases. (18)F-fluoromethylcholine kinetics were studied by nonlinear regression fitting of several single- and 2-tissue plasma input models to the time-activity curves. Model selection was based on the Akaike information criterion and measures of robustness. In addition, the performance of several simplified methods, such as standardized uptake value (SUV), was assessed.. Best fits were obtained using an irreversible compartment model with blood volume parameter. Parent fractions were 0.12 ± 0.4 after 20 min, necessitating individual metabolite corrections. Correspondence between venous and arterial parent fractions was low as determined by the intraclass correlation coefficient (0.61). Results for image-derived input functions that were obtained from volumes of interest in blood-pool structures distant from tissues of high (18)F-fluoromethylcholine uptake yielded good correlation to those for the blood-sampling input functions (R(2) = 0.83). SUV showed poor correlation to parameters derived from full quantitative kinetic analysis (R(2) < 0.34). In contrast, lesion activity concentration normalized to the integral of the blood activity concentration over time (SUVAUC) showed good correlation (R(2) = 0.92 for metabolite-corrected plasma; 0.65 for whole-blood activity concentrations).. SUV cannot be used to quantify (18)F-fluoromethylcholine uptake. A clinical compromise could be SUVAUC derived from 2 consecutive static PET scans, one centered on a large blood-pool structure during 0-30 min after injection to obtain the blood activity concentrations and the other a whole-body scan at 30 min after injection to obtain lymph node activity concentrations.

Topics: Aged; Calibration; Choline; Humans; Kinetics; Lymph Nodes; Lymphatic Metastasis; Male; Middle Aged; Neoplasm Metastasis; Positron-Emission Tomography; Prostatectomy; Prostatic Neoplasms; Radiopharmaceuticals; Regression Analysis; Time Factors; Tomography, X-Ray Computed

The aim of this study was to assess the value of combining MRI and F-fluorocholine (FCH) PET/CT for patients with a biochemical relapse (BR) after prostate radiotherapy or brachytherapy.. All patients with a BR (BR definition: nadir prostate-specific antigen, +2 ng/mL) had a multiparametric MRI and FCH PET/CT if there was no clinical sign of relapse. Identification of the relapse was considered positive if both imaging techniques were concordant or in case of pathological relapse confirmation.. Sixty-five consecutive patients were analyzed. Initial treatment was external beam radiation therapy (EBRT; n = 40), surgery followed by EBRT (n = 11), or brachytherapy (n = 14). Gleason score was 6 in 23 patients, 7 in 35 patients, and 8 to 10 in 7 patients. Median prostate-specific antigen value at the time of relapse was 7.6 ng/mL. Determination of relapse location was identified in 46 patients (70.7%). Relapses were only local in 24 patients (37%), nodal in 16 (24.6%), and distant in 9 (14%). In 4 cases, MRI showed a local relapse not seen by FCH PET/CT. Among the 24 patients with an isolated local relapse, 13 underwent a confirmatory biopsy and 9 were positive. At the end, only 7 patients (11%) could have a salvage local treatment: cryotherapy of the prostate in 6 cases and 1 nodal EBRT.. In case of BR after radiotherapy or brachytherapy, combining MRI and FCH PET/CT could identify the site of relapse in 70% of patients. This could facilitate the selection of the patients for local salvage treatment.

Topics: Aged; Case-Control Studies; Choline; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Multimodal Imaging; Neoplasm Recurrence, Local; Positron-Emission Tomography; Prostatic Neoplasms; Radiopharmaceuticals; Tomography, X-Ray Computed