gadoxetic-acid-disodium and Neuroendocrine-Tumors

The following is an illustrative review of common pitfalls in liver MRI that may challenge interpretation. This article reviews common technical and diagnostic challenges encountered when interpreting dynamic multiphasic T

Topics: Algorithms; Artifacts; Contrast Media; Diffusion Magnetic Resonance Imaging; False Positive Reactions; Gadolinium DTPA; Hemorrhage; Humans; Image Enhancement; Image Interpretation, Computer-Assisted; Image Processing, Computer-Assisted; Imaging, Three-Dimensional; Iron Overload; Liver; Liver Cirrhosis; Liver Neoplasms; Magnetic Resonance Imaging; Motion; Neoplasm Metastasis; Neuroendocrine Tumors; Reproducibility of Results; Respiration

We evaluated the rate of successful characterization of gastroenteropancreatic neuroendocrine tumors (NETs) present with an increased somatostatin receptor, comparing CE-CT with CE-MRI, each in correlation with DOTATOC-PET.. 8 patients with GEP-NET were imaged using CE-MRI (Gd-EOB-DTPA), CE-CT (Imeron 400) and DOTATOC-PET. Contrast-enhancement of normal liver-tissue and metastasis was quantified with ROI-technique. Tumor delineation was assessed with visual-score in blind-read-analysis by two experienced radiologists.. Out of 40 liver metastases in patients with NETs, all were detected by CE-MRI and the lesion extent could be adequately assessed, whereas CT failed to detect 20% of all metastases. The blind-read-score of CT in arterial and portal phase was median -0.65 and -1.4, respectively, and 2.7 for delayed-MRI. The quantitative ROI-analysis presented an improved contrast-enhancement-ratio with a median of 1.2, 1.6 and 3.3 for CE-CT arterial, portal-phase and delayed-MRI respectively.. Late CE-MRI was superior to CE-CT in providing additionally morphologic characterization and exact lesion extension of hepatic metastases from neuroendocrine tumor detected with DOTATOC-PET. Therefore, late enhanced Gd-EOB-DTPA-MRI seems to be the adequate imaging modality for combination with DOTATOC-PET to provide complementary (macroscopic and molecular) tumor characterization in hepatic metastasized NETs.

Topics: Contrast Media; Female; Gadolinium DTPA; Humans; Indium Radioisotopes; Iopamidol; Magnetic Resonance Imaging; Male; Neuroendocrine Tumors; Octreotide; Positron-Emission Tomography; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity; Statistics as Topic; Tomography, X-Ray Computed

To identify the imaging and clinical features of hepatic neuroendocrine tumors (NETs) associated with peritumoral hyperintensity in the hepatobiliary phase of gadoxetic acid-enhanced magnetic resonance (MR) imaging.. Fifty-seven patients with hepatic NETs were enrolled. Based on the degree of peritumoral hyperintensity, patients were divided into three groups: group 0 (no peritumoral hyperintensity), group 1 (lower peritumoral hyperintensity), and group 2 (higher peritumoral hyperintensity). The imaging and clinical findings were compared among the three groups.. Apparent diffusion coefficient (ADC) values of group 2 were significantly lower than those of group 0 and group 1. Atypical (cholangiocarcinoma-like) enhancement pattern in the arterial phase was significantly more frequently observed in group 2 as compared to that in group 0 and group 1. Group 2 patients showed significantly poorer progression-free survival than group 0 patients.. Hepatic NETs with greater peritumoral hyperintensity exhibit greater malignant potential.

Topics: Adult; Aged; Aged, 80 and over; Contrast Media; Diagnosis, Differential; Diffusion Magnetic Resonance Imaging; Female; Gadolinium DTPA; Humans; Image Enhancement; Liver Neoplasms; Male; Middle Aged; Neuroendocrine Tumors; Progression-Free Survival

Metastatic gastroenteropancreatic neuroendocrine neoplasms (mGEP-NEN) are indolent malignancies which undergo frequent imaging follow-up. Hepatocellular phase (HCP) MR with hepatocellular-specific contrast agent is widely used to evaluate mGEP-NEN liver metastases but is commonly performed after a 20-min delay which prolongs scan time. The purpose of this study was to evaluate if HCP MR at 15 min offers comparable performance to 20-min delay for patients with mGEP-NEN undergoing routine imaging surveillance.. In this IRB-approved retrospective study, we evaluated 52 patients with mGEP-NEN who were imaged for routine surveillance with gadoxetate disodium (Eovist. No differences were observed for subjective image quality (R1 p = 0.86, R2 p = 0.17) or lesion conspicuity (R1 p = 0.56, R2 p = 0.74) at 15 min and 20 min for either reader. Individual-reader concordance correlation coefficient between 15 and 20 min was high for number of metastases detected (R1 = 0.9842, R2 = 0.9579) and diameter of largest metastasis (R1 = 0.9629, R2 = 0.8859).. HCP imaging at 15 min provides similar diagnostic yield to standard 20-min delay, which may help reduce the scan time and costs, and improve throughput and patient satisfaction.

Topics: Carcinoma, Hepatocellular; Contrast Media; Gadolinium DTPA; Humans; Liver Neoplasms; Magnetic Resonance Imaging; Neuroendocrine Tumors; Retrospective Studies

To compare the diagnostic accuracy of dynamic contrast-enhanced phases, hepatobiliary phase (HBP), and diffusion-weighted imaging (DWI) for the detection of liver metastases from neuroendocrine tumor (NET).. Sixty-seven patients with suspected NET liver metastases underwent gadoxetic acid-enhanced MRI. Three radiologists read four imaging sets separately and independently: DWI, T2W+dynamic, T2WI+HBP, and DWI+HBP. Reference standard included all imaging, histological findings, and clinical data. Sensitivity and specificity were calculated and compared for each imaging set. Interreader agreement was evaluated by intraclass correlation coefficient (ICC). Univariate logistic regression was performed to evaluate lesion characteristics (size, ADC, and enhancing pattern) associated to false positive and negative lesions.. Six hundred twenty-five lesions (545 metastases, 80 benign lesions) were identified. Detection rate was significantly higher combining DWI+HBP than the other imaging sets (sensitivity 86% (95% confidence interval (CI) 0.845-0.878), specificity 94% (95% CI 0.901-0.961)). The sensitivity and specificity of the other sets were 82% and 65% for DWI, 88% and 69% for T2WI, and 90% and 82% for HBP+T2WI, respectively. The interreader agreement was statistically higher for both HBP sets (ICC = 0.96 (95% CI 0.94-0.97) for T2WI+HBP and ICC = 0.91 (95% CI 0.87-0.94) for DWI+HBP, respectively) compared with that for DWI (ICC = 0.76 (95% CI 0.66-0.83)) and T2+dynamic (ICC = 0.85 (95% CI 0.79-0.9)). High ADC values, large lesion size, and hypervascular pattern lowered the risk of false negative.. Given the high diagnostic accuracy of combining DWI+HBP, gadoxetic acid-enhanced MRI is to be considered in NET patients with suspected liver metastases. Fast MRI protocol using T2WI, DWI, and HBP is of interest in this population.. • The combined set of diffusion-weighted (DW) and hepatobiliary phase (HBP) images yields the highest sensitivity and specificity for neuroendocrine liver metastasis (NELM) detection. • Gadoxetic acid should be the contrast agent of choice for liver MRI in NET patients. • The combined set of HBP and DWI sequences could also be used as a tool of abbreviated MRI in follow-up or assessment of treatment such as somatostatin analogs.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Biometry; Contrast Media; Diffusion Magnetic Resonance Imaging; False Positive Reactions; Female; Gadolinium DTPA; Gastrointestinal Tract; Humans; Image Processing, Computer-Assisted; Intestinal Neoplasms; Liver Neoplasms; Male; Middle Aged; Neuroendocrine Tumors; Pancreatic Neoplasms; Regression Analysis; Sensitivity and Specificity; Stomach Neoplasms; Young Adult

Topics: Abdomen; Abdominal Neoplasms; Adult; Aged; Aged, 80 and over; Cohort Studies; Contrast Media; Female; Gadolinium DTPA; Hepatocytes; Humans; Image Enhancement; Magnetic Resonance Imaging; Male; Middle Aged; Neuroendocrine Tumors; Pelvic Neoplasms; Pelvis; Retrospective Studies

To compare hepatocellular phase imaging after intravenous gadoxetate disodium with other MRI pulse sequences and with extracellular agent for assessing hepatic metastases from gastroenteropancreatic neuroendocrine neoplasms (GEP-NEN).. In this IRB-approved, HIPAA-compliant retrospective study, we included 30 patients (15 women, mean age: 58 years, range 44-77 years) with GEP-NEN metastatic to the liver, who underwent MRI with gadoxetate disodium. Six MRI sequences were reviewed by two radiologists to score tumor-liver interface (TLI) on a 5-point scale, to assess lesion detectability in different liver segments (divided into 3 zones/patient), and to measure lesion size. Contrast-to-noise ratio (CNR) was calculated on each sequence. In 19 patients, lesion size and CNR on dynamic imaging with gadopentetate dimeglumine was compared with hepatocellular phase. Wilcoxon signed-rank test was used to compare TLI scores, lesion size, and median CNR, using Bonferroni correction for multiple testing. Interobserver agreement for TLI was analyzed using Krippendorff's alpha, and for lesion size using concordance correlation coefficient (CCC) and mean relative difference.. Hepatocellular phase had the best TLI (mean TLI for reader 1 = 1.2, reader 2 = 1.3) compared to all other sequences (p < 0.0001) with excellent interobserver agreement (Krippendorff's alpha = 1.0), maximum lesion detectability (61/90 zones), highest interobserver agreement for lesion measurement (CCC 0.9875 and smallest mean relative difference - 1.567%), and highest median CNR (31.2, p < 0.008). Hepatocellular phase also had the highest CNR when compared with gadopentetate imaging.. Hepatocellular phase imaging offers significant advantages for assessment of hepatic metastasis in GEP-NEN, and should be routinely considered for follow-up of these patients.

Topics: Adult; Aged; Contrast Media; Female; Gadolinium DTPA; Humans; Intestinal Neoplasms; Liver Neoplasms; Magnetic Resonance Imaging; Male; Middle Aged; Neuroendocrine Tumors; Pancreatic Neoplasms; Retrospective Studies; Stomach Neoplasms

To describe the findings of magnetic resonance (MR) imaging of hepatic neuroendocrine tumors (hNET) and to identify the features that differentiate secondary from primary tumors.. This retrospective study was approved by the institutional review board, and the requirement for informed consent was waived. Between August 2008 and December 2014, 50 patients with pathologically proven hNETs who underwent gadoxetic acid-enhanced MR imaging with diffusion-weighted images were included. The patients were divided into two groups according to whether they had primary (n = 17) or secondary (n = 33) hNETs. Qualitative values based on a consensus between two observers [morphologic findings, signal intensity, and enhancement pattern (poor or indeterminate; hepatocellular carcinoma-like or cholangiocarcinoma-like)], and quantitative values (apparent diffusion coefficient) were evaluated as predictors of secondary hNETs using multivariable logistic regression and receiver operating characteristic (ROC) analysis.. In multivariate analysis, the presence of multiple lesions (p = 0.011), a tumor size less than 6.3 cm (p = 0.001), and a hepatocellular carcinoma-like enhancement pattern (p = 0.031) were significant independent factors for differentiating secondary from primary hNETs, and achieved a sensitivity of 91%, a specificity of 82%, and an accuracy of 88%, with a value of the area under the ROC curve of 0.931.. Using these specific MR imaging criteria, secondary hNETs could be differentiated from primary hNETs with a high degree of accuracy in patients with histopathologically proven hNETs.

Topics: Adult; Aged; Aged, 80 and over; Case-Control Studies; Contrast Media; Diagnosis, Differential; Female; Gadolinium DTPA; Humans; Image Enhancement; Liver; Liver Neoplasms; Magnetic Resonance Imaging; Male; Middle Aged; Neoplasms, Second Primary; Neuroendocrine Tumors; Reproducibility of Results; Retrospective Studies; Sensitivity and Specificity; Young Adult

To evaluate the association of therapy-related changes in imaging parameters with progression-free survival (PFS) of patients with unresectable liver metastases from neuroendocrine tumors (NETLMs).. Forty-five radioembolized patients (median age: 62 years; range: 43-75) received a pre- and 3 months posttherapeutic magnetic resonance imaging (MRI) examination. The latter were evaluated for tumor size, arterial enhancement, and necrosis pattern. Influences of therapy-related changes on PFS were analyzed. Statistical analysis included Student's t-test, Wilcoxon test, Cox regression analysis, and Kaplan-Meier curves.. The median percentage decrease in sum of diameters was 9.7% (range: 43.9% decrease to 15.4% increase). Twenty-one patients (47%) showed increased necrosis. Three parameters were associated with significantly longer PFS: a decrease of diameter (hazard ratio [HR]: 0.206; 95% confidence interval [CI]: 0.058-0.725; P = 0.0139), a decrease in tumor arterial enhancement (HR: 0.143; 95% CI: 0.029-0.696; P = 0.0160), and an increase in necrosis after 3 months (HR: 0.321; 95% CI: 0.104-0.990; P = 0.0480). Multivariate analysis revealed that changes in diameter and arterial enhancement have complementary information and are associated independently with long PFS.. A decrease both in sum of diameters and arterial enhancement of metastases, as well as an increase in necrosis, are associated with significantly longer PFS after radioembolization.

Topics: Adult; Aged; Contrast Media; Disease-Free Survival; Embolization, Therapeutic; Female; Gadolinium DTPA; Humans; Image Interpretation, Computer-Assisted; Liver Neoplasms; Magnetic Resonance Imaging; Male; Microspheres; Middle Aged; Neoplasm Grading; Neuroendocrine Tumors; Retrospective Studies; Treatment Outcome; Yttrium Radioisotopes

To evaluate the value of abdominal MRI with diffusion-weighted (DW) imaging for differentiation of solid-type serous cystic neoplasm (SCN) from neuroendocrine tumour (NET) in the pancreas compared with that of CT.. Ten solid-type SCNs and 15 NETs were included in the study. Qualitative and quantitative analyses were performed, and two observers independently reviewed CT and MRI images for diagnosis of solid-type SCNs. Fisher's exact test and Mann-Whitney U-test, diagnostic performance [receiver operating characteristic (ROC) curve analysis] were evaluated.. SCNs showed more frequently hypo-attenuation on unenhanced CT images and marked hyperintensity on T2-weighted images compared with NETs (p < 0.01). The density of the tumour on unenhanced CT images and the apparent diffusion coefficient (ADC) value of the tumour were significantly different between SCNs (mean 18.5 HU; mean 2.45 × 10(-3) mm(2)/s) and NETs (mean 39.2 HU; mean 1.51 × 10(-3) mm(2)/s; p < 0.001). In the differentiation of SCNs from NETs, diagnostic performance of MRI with DW images was significantly higher than that of CT imaging (p < 0.01).. Abdominal DW-MRI shows a higher diagnostic accuracy than abdominal CT imaging in the differentiation of solid-type SCNs from NETs.

Topics: Adolescent; Adult; Aged; Contrast Media; Diagnosis, Differential; Diffusion Magnetic Resonance Imaging; Female; Gadolinium DTPA; Humans; Image Enhancement; Male; Middle Aged; Neuroendocrine Tumors; Pancreas; Pancreatic Cyst; Pancreatic Neoplasms; Retrospective Studies; ROC Curve; Sensitivity and Specificity; Tomography, X-Ray Computed; Young Adult

To evaluate a simultaneous PET/MRI approach to imaging patients with neuroendocrine tumor using a combination of (68)Ga-DOTA-TOC as a PET contrast agent and gadoxetate disodium as a hepatobiliary MRI contrast agent.. Ten patients with neuroendocrine tumor with known or suspected hepatic disease were imaged using a (68)Ga-DOTA-TOC PET/CT immediately followed by a 3.0T time-of-flight PET/MRI, using a combined whole body and liver specific imaging. The presence of lesions and DOTA-TOC avidity were assessed on CT, PET from PET/CT, diffusion weighted imaging, hepatobiliary phase imaging (HBP), and PET from PET/MRI. Maximum standardized uptake values (SUVmax) in hepatic lesions and nodal metastases were compared between PET/CT and PET/MRI, as were detection rates using each imaging approach.. A total of 101 hepatic lesions were identified, 47 of which were DOTA-TOC avid and able to be individually measured on both PET/CT and PET/MRI. HBP imaging had a higher sensitivity for detection of hepatic lesions compared to CT or PET (99% vs. 46% and 64%, respectively; p values <0.001). There was a strong correlation between SUVmax of liver lesions obtained with PET/CT compared to PET/MR imaging (Pearson's correlation = 0.91). For nodal disease, CT had a higher sensitivity compared to whole body MRI (p = 0.015), although PET acquired from PET/MRI detected slightly more lesions compared to PET from PET/CT.. A simultaneous PET/MRI using both (68)Ga-DOTA-TOC and gadoxetate disodium was successful in whole body staging of patients with neuroendocrine tumor. HBP imaging had an increased detection rate for hepatic metastases.

Topics: Adult; Aged; Contrast Media; Diagnosis, Differential; Female; Gadolinium DTPA; Gallium Radioisotopes; Humans; Image Enhancement; Liver; Liver Neoplasms; Magnetic Resonance Imaging; Male; Middle Aged; Multimodal Imaging; Neuroendocrine Tumors; Octreotide; Organometallic Compounds; Positron-Emission Tomography; Radiopharmaceuticals; Reproducibility of Results; Whole Body Imaging

Parenchyma-preserving resection for the treatment of benign pancreatic neuroendocrine tumors (NETs) has been tried, and preoperative prediction of benign pancreatic NET is important. Recently, diffusion-weighted imaging (DWI) of abdomen magnetic resonance imaging (MRI) has been used to characterize benign and malignant tumors and DWI might be helpful in prediction of benign pancreatic NETs.. To evaluate the value of gadoxetic acid-enhanced MRI and DWI in predicting benign pancreatic NETs for determination of parenchyma-preserving resection.. Our ethics committee approved this study with a waiver of informed consent given its retrospective design. We searched radiology and pathology databases from November 2010 to July 2012 to identify patients who underwent surgery for pancreatic NETs (<4 cm). Twenty patients in the benign group and 14 patients in the non-benign group were included in this study. Two radiologists analyzed the morphologic features, signal intensity on MR images including DWI (b = 800), and dynamic enhancement pattern of the tumors with consensus. The tumor-to-parenchyma ratio and tumor apparent diffusion coefficients (ADCs) were quantitatively assessed.. The benign pancreatic NETs were more often round (7/20, 35%) or ovoid (13/20, 65%) in shape and less hypovascular on the arterial phase (3/20, 15%) than were the non-benign pancreatic NETs (1/14, 7.1% and 5/14, 35.8%; 7/14, 50% respectively; P < 0.05). Main pancreatic duct dilatation by tumors was demonstrated only in non-benign pancreatic NETs (4/14, 28.4%; P = 0.021). ADC values and ratios were significantly different between benign pancreatic NETs (mean, 1.48 × 10(-3 )mm(2)/sec, 1.11 ± 0.25, each) and non-benign pancreatic NETs (mean, 1.04 × 10(-3 )mm(2)/sec, 0.74 ± 0.13, each) (P < 0.01). Other qualitative and quantitative analyses between benign and non-benign pancreatic NETs were not significantly different (P > 0.05).. Abdominal MRI with DWI may be useful for differentiating benign pancreatic NETs from non-benign pancreatic NETs, which might be helpful for determination of parenchyma-preserving resection.

Topics: Adolescent; Adult; Aged; Contrast Media; Diffusion Magnetic Resonance Imaging; Female; Gadolinium DTPA; Humans; Male; Middle Aged; Neoplasm Grading; Neuroendocrine Tumors; Pancreatic Neoplasms; Predictive Value of Tests; Retrospective Studies; Young Adult

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

To compare fused gadoxetate-enhanced Ga-68-DOTANOC PET/MRI and Ga-68-DOTANOC PET/DWI (diffusion-weighted imaging) for the assessment of abdominal neuroendocrine tumours (NETs).. Eighteen patients with suspected or histologically proven NETs of the abdomen were enrolled in this retrospective study. All patients underwent Ga-68-DOTANOC PET/CT for a primary search, staging, or restaging, and received an additional MRI, including dynamic gadoxetate-enhanced T1-weighted sequences and DWI (b-values 50, 300 and 600). Co-registered gadoxetate-enhanced PET/MRI and PET/DWI were separately analysed for NET lesions by a nuclear medicine physician and a radiologist in consensus. Sensitivity and specificity were calculated on a per-region, per-organ and per-patient basis.. Eighty-seven out of 684 anatomical regions, and 23 out of 270 organs, were NET-positive in 14 out of 18 patients. Region-based sensitivities and specificities were 97.7 % and 99.7 % for gadoxetate-enhanced PET/MRI and 98.9 % and 99.7 % for PET/DWI. Organ-based sensitivities and specificities were 91.3 % and 99.6 % for gadoxetate-enhanced PET/MRI and 95.7 % and 99.6 % for PET/DWI. Finally, patient-based sensitivities and specificities were 100 % and 100 % for gadoxetate-enhanced PET/MRI and 100 % and 75 % for PET/DWI. Sensitivities and specificities of the two methods did not differ significantly.. Gadoxetate-enhanced Ga-68-DOTANOC PET/MRI and Ga-68-DOTANOC PET/DWI are equally useful for the assessment of abdominal NETs.. • Positron emission tomography and magnetic resonance imaging can both assess neuroendocrine tumours. • Fusion of PET/MR imaging provides helpful information. • Gadoxetate-enhanced Ga-68-DOTANOC PET/MRI and Ga-68-DOTANOC PET/DWI assess neuroendocrine tumours equally well. • PET/DWI is inherently simpler than gadoxetate-enhanced PET/MRI. • Only benign hepatic lesions pose a potential diagnostic dilemma for PET/DWI.

Topics: Abdomen; Adolescent; Adult; Aged; Aged, 80 and over; Child; Contrast Media; Diffusion Magnetic Resonance Imaging; Female; Gadolinium DTPA; Gallium Radioisotopes; Humans; Image Processing, Computer-Assisted; Male; Middle Aged; Multimodal Imaging; Neuroendocrine Tumors; Organometallic Compounds; Positron-Emission Tomography; Reproducibility of Results; Retrospective Studies; Sensitivity and Specificity; Young Adult

To assess the detection rate of liver lesions in patients with advanced gastroenteropancreatic neuroendocrine carcinomas (GEP-NETs) using echo planar (EP) DWI (diffusion weighted imaging) as compared to standard FSE T2 wi and FFE T1 wi with i.v. (Gd-EOB)-DTPA.. This prospective single-institution study included 55 patients with liver involvement confirmed by GEP-NETs 1.5T MRI system, using FSE T2, EP DWI and FFE T1 with i.v. (Gd-EOB)-DTPA. The potential differences between detection rates of liver deposits using 3 different MR approaches and between groups of patients were compared.. Mean number of liver deposits: FSE T2=20.7, FFE T1=25.7 and tested EP DWI=24.0. No significant difference was found in overall detection rate of liver deposits seen in 3 different techniques. A significant difference in detection rate of liver deposits was noted between male vs. female and secreting vs. non-secreting cancers. There was nearly perfect agreement between both observers, and each of the tested MRI approaches in regards to number of detected liver lesions (Cohen's kappa=0.848-1).. There were no significant differences among the 3 different MRI approaches in detection rates of liver deposits. Perfect agreement with high detection rate of liver deposits provides a rationale for the use of EP DWI in follow-up studies in GEP-NET patients.

Topics: Adult; Aged; Contrast Media; Echo-Planar Imaging; Female; Gadolinium DTPA; Gastrointestinal Neoplasms; Humans; Infusions, Intravenous; Liver Neoplasms; Male; Middle Aged; Neuroendocrine Tumors; Observer Variation; Prospective Studies

To evaluate the feasibility of quantifying hepatic perfusion and function by using dynamic contrast material-enhanced (DCE) magnetic resonance (MR) imaging with the hepatobiliary contrast agent gadoxetic acid and a dual-inlet two-compartment uptake model.. The study was approved by the local institutional review board, and written informed consent was obtained from all patients. Data were acquired between October 2008 and November 2009 in 24 patients with hepatic metastases from neuroendocrine tumors (13 men, 11 women; mean age, 59.8 years). DCE MR imaging was performed at 3.0 T with a standard dose of gadoxetic acid and a three-dimensional sequence, with 48 sections of data acquired every 2.2 seconds for 5 minutes. For each patient, a plasma flow map was calculated by means of deconvolution and the model was fitted to six region-of-interest curves. Results were evaluated with goodness-of-fit analysis and, in normal-appearing liver tissue, by comparing perfusion parameters with those reported in the literature. Interobserver effects in the selection of arterial and venous input functions were assessed.. With an arterial delay parameter, the model provided a good fit to all data. Values for arterial and venous plasma flow and extracellular volume in normal-appearing liver tissue were comparable to those in the literature. The mean intracellular uptake rate is 3.4/100/min with a standard deviation of 1.9/100/min The model also provided a good fit in all tumor data, producing high arterial flow fraction (87%) and lower uptake (1.7/100/min) . Bias due to observer-dependent differences in the selection of the input functions was negligible.. The analysis of dynamic gadoxetic acid-enhanced MR images with the dual-inlet two-compartment uptake model presents a new and practical approach for measuring arterial and venous perfusion and hepatic function in a single acquisition.

Topics: Adult; Aged; Aged, 80 and over; Contrast Media; Feasibility Studies; Female; Gadolinium DTPA; Humans; Liver Neoplasms; Magnetic Resonance Imaging; Male; Middle Aged; Neuroendocrine Tumors; Prospective Studies