Relationships between pancreaticobiliary ductal anatomy and pancreatic ductal and parenchymal histology.

To determine whether ductal or parenchymal histologic abnormalities were related to the type of openings of the pancreatic duct and common bile duct into the duodenum, 390 unfixed human postmortem en bloc pancreaticoduodenal specimens were examined anatomically, radiographically, and histologically. In 353 specimens, ductal openings were classifiable: 25% had a well-defined ampulla, 18% a long common channel, 31% a short common channel, 7% an interposed septum, and 19% had separate openings for the pancreatic and bile ducts. Ductal histologic abnormalities were present in 25% of the specimens and most (77%) were found in the pancreatic head. When ductal openings were grouped according to the presence or lack of a prominent common channel, ductal epithelial abnormalities were more common in the absence of a prominent common channel (30% vs. 19%, p less than 0.04). Papillary epithelial hyperplasia was associated only with the absence of a prominent common channel (P = 0.02). Histologic abnormalities were more common in the elderly (P less than 0.005) but were not associated with cause of death or the presence of the minor pancreatic duct. Lack of a common channel is associated with abnormal ductal epithelium. This anatomic arrangement may be a factor in pancreatic carcinogenesis.