Endocrine Abstracts

Background: Pancreatic neuroendocrine neoplasms (panNENs) are heterogeneous, with grade (G) defined by Ki67 proliferation index (<3% G1, 3-20% G2, >20% G3) or mitotic rate. The G3 NEN subgroup is further divided into well differentiated neuroendocrine tumors (NETs) and poorly differentiated neuroendocrine carcinomas (NEC). Grade progression can occur over time, with low-to-high grade progression (L-to-H; G1/2 to G3) the most clinically relevant form. It is associated w...

Background: Grade 3 pancreatic neuroendocrine tumor (G3-PanNET) and neuroendocrine carcinoma (PanNEC) are both defined by Ki67>20% and/or mitoses >20 per 2mm2. PanNET and PanNEC are thought to be molecularly distinct entities and progression from PanNET to PanNEC is considered rare. MEN1, ATRX, DAXX, and TSC1/2 mutations are common in PanNET, while TP53, RB1, KRAS, and SMAD4 mutations are typical of PanNEC. Immunostains for ATRX/DAXX/p53/Rb aid in the classification of...