PURPOSE: Most well-differentiated @entity5 ( @entity2360 -NET) of the enteropancreatic system are low-intermediate grade (G1, G2). Elevated proliferation demonstrated by either a brisk mitotic rate (>20/10 high power fields) or high Ki-67 index (>20%) defines a group of @entity146 designated as high-grade (G3) @entity3270 ( @entity3270 ). High-grade @entity3270 is equated with @entity3270 ( @entity3270 ) and is associated with a dismal outcome. Progression of @entity2360 to a high-grade neuroendocrine @entity5 very rarely occurs and their clinicopathologic and molecular features need to be characterized. EXPERIMENTAL DESIGN: We investigated 31 cases of @entity2360 with evidence of a component of a high-grade @entity5 . The primary sites included pancreas, small bowel, bile duct, and rectum. Histopathology of the cases was retrospectively reviewed and selected IHC and gene mutation analyses performed. RESULTS: The high-grade component occurred either within the primary @entity5 (48%) or at metastatic sites (52%). The clinical presentation, radiographic features, biomarkers, and the genotype of these @entity2360 with high-grade component remained akin to those of G1-G2 @entity2360 . The median disease-specific survival (DSS) was 55 months (16-119 months), and 2-year and 5-year DSS was 88% and 49%, respectively-significantly better than that of a comparison group of true @entity3270 (DSS 11 months). CONCLUSIONS: Mixed grades can occur in @entity2360 , which are distinguished from PD-NECs by their unique phenotype, proliferative indices, and the genotype. This phenomenon of mixed grade in @entity2360 -NET provides additional evidence to the growing recognition that the current WHO G3 category contains both @entity2360 as well as PD-NECs. Clin Cancer Res; 1-7.   2015 AACR.

Well-Differentiated @entity5 with a Morphologically Apparent High-Grade Component: A Pathway Distinct from Poorly Differentiated XXXX .

@entity5 :: ('MESH:D009369', 'Disease') :: ['tumor', 'neuroendocrine tumors', 'neoplasm'] @entity2360 :: ('MESH:D006527', 'Disease') :: ['WD-NETs', 'WD'] @entity3270 :: ('MESH:D018278', 'Disease') :: ['poorly differentiated NEC', 'NEC', 'PD-NEC', 'neuroendocrine carcinoma'] @entity146 :: ('MESH:D001523', 'Disease') :: ['aggressive neoplasms']
@entity3270 :: (MESH:D018278,Disease) :: ['Neuroendocrine Carcinomas']
