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Pancreatic neuroendocrine neoplasms (pNEN) are rare malignancies arising from neuroendocrine cells of the pancreas. Functional tumors can present with specific clinical syndromes due to hormonal secretion. These tumors can present as incidental findings on imaging performed for unrelated purposes or they are diagnosed when workup is initiated in patients with specific syndromes or metastases. This article presents an overview of available imaging techniques focusing on computed tomography and magnetic resonance imaging. Recommendations regarding examination protocols are given. Typical imaging features of pNEN and metastases are described. Their potential value for the evaluation of prognosis as well as tumor response under treatment is discussed.

Background The ability to non-invasively analyze tumor aggressiveness is an important predictor for individual treatment stratification and patient outcome in prostate cancer (PCA). Purpose To evaluate: (i) whether apparent diffusion coefficient (ADC), the T2 signal intensity (SI), and a combination of both parameters allow for an improved discrimination of Gleason Score (GS) ≥7 (intermediate and high risk) and GS Material and Methods Prostatectomy specimens of 66 patients (mean age, 63 ± 5.6 years; 104 PCA foci) with a preceding multiparametric 1.5 T endorectal coil magnetic resonance imaging (MRI) were included. ADC ( b values = 0, 100, 400, 800 s/mm2), standardized T2 (T2s), and the ADC/T2s ratio were tested for correlation with GS applying multivariate analysis. ADC cutoff values were calculated for prediction of GS and pGG, and logarithm of the odds (LOGIT) was used to express the probability for GS and pGG. Diagnostic accuracy was assessed by ROC analysis. Results We found an almost linear negative relationship of ADC for GS ≥7 ( P = 0.002). The effect of ADC for GS ≥7 (adjusted odds ratio = 0.995) was almost identical for peripheral and transition zone PCA ( P = 0.013 and P −3 mm2/s indicated a GS ≥7 (90.5% sensitivity, 62.5% specificity). Within the group of GS = 7 PCA, an ADC > 0.762 × 10−3 mm2/s indicated a pGG of 3 (AUC = 69.6%). Conclusion T2s and the ADC/T2s ratio do not provide additional information regarding prediction of GS. ADC values have a good discriminatory power to distinguish tumors with GS ≥7 from GS