Intraductal papillary mucinous neoplasm (IPMN) of the pancreas: its histopathologic difference between 2 major types.

Intraductal papillary mucinous neoplasm (IPMN) is a unique pancreatic neoplasm developing in the ductal system. Two major histologic subtypes have been reported, that is the gastric type and the intestinal type. However, their histopathologic features, especially those of the gastric type, have not been fully described.

Intraductal papillary mucinous neoplasm (IPMN) of the gastric-type with focal nodular growth of the arborizing papillae: a case of high-grade transformation of the gastric-type IPMN.

We present a case of intraductal papillary mucinous neoplasm (IPMN) of the pancreas, demonstrating a process of high-grade transformation of the gastric-type IPMN. An 83-year-old Japanese woman underwent pylorus-preserving pancreatoduodenectomy for removal of a multicystic mass of the pancreas head, which had been followed up for 7 years. The removed tumor was a low-grade gastric-type IPMN spreading in the branch ducts, focally forming an intraluminal nodular lesion.