PanNET : Origins
Origins of pancreatic neuroendocrine tumors (PanNETs): PanNETs were previously called Islet Cell Tumors, although there was no conclusive evidence that they arose from pancreatic islets. PanNETs frequently contain ductules and produce hormones like gastrin and vasoactive intestinal peptide that are normally not found in pancreas. Some speculate that they are ductular in origin. Recent evidence suggests that they arise from stem cells capable of neuroendocrine differentiation. Genetic Syndromes: About 10-20% of PanNETs are associated with genetic syndromes, including MEN type1, vHL, neurofibromatosis type 1, tuberous sclerosis, glucagon cell hyperplasia, and familial insulinomatosis. About this image: Well-differentiated PanNET showing uniform tumor cells arranged in anastomosing cords and trabeculae separated by delicate vascular stroma.