Computed tomography and magnetic resonance imaging features of lipid-rich neuroendocrine tumors of the pancreas

Figure 1 Lipid-rich pancreatic neuroendocrine tumor in a 64-year-old woman. A: Axial early phase enhanced computed tomography shows a 30 mm well-circumscribed tumor (arrow) with thick and marked contrast enhancement only at the periphery; B: The tumor shows heterogeneous high signal intensity (arrow) on fat-suppressed T2-weighted images (4200/71); C and D: In-phase (5.8/2.4, 10°) (C) and out-of-phase (5.8/1.2, 10°) images with 3D technique (D) show a substantial drop in tumor signal intensity (arrow) from the in-phase (209.6) to the out-of-phase (137.5) image, resulting in a signal intensity index of 34.4%; E: The subtraction image shows apparent high signal intensity (arrow), indicating the presence of lipid component; F: Grossly, the pancreatic NET is a well-circumscribed yellowish color lesion; G: Microscopically, the tumor cells have abundant microvesicular cytoplasm; H: Adipose differentiation-related protein (ADRP) is expressed in the cytoplasm of tumor cells. The staining area is a microvesicular pattern as droplets.