Anatomical and Morphological Features of the Fetal Human Pancreaticobiliary Ductal Union.

To investigate pancreaticobiliary ductal anatomy during developmental stages, gallbladders, common bile ducts, pancreatic ducts and their interface with the duodenum were studied in 36 human fetuses between 4-6 weeks postconceptual age were studied. For histological examination, sections were cut continuously from the paraffin-embedded tissue block and stained with hematoxylin and eosin. The expression of proliferating cell nuclear antigen in the gallbladder was examined with immunohistochemistry. Among 36 cases, three shapes of the greater duodenal papilla were found: hemispheroid (58.1%), circular cylinder (25%), and flat shape (16.9%). For the location of the greater duodenal papillas, more than half (69.4%) of the cases were in the middle descendant duodenum. Seven cases (19.4%) were in the lower descendant duodenum. Three cases (8.3%) were in the upper descendant duodenum, and one (2.9%) was in the distal descending part of duodenum. There were four types of the pancreaticobiliary ductal union: "Y" in 24 cases(66.7%), "U" in 4 cases (11.1%),"V" in 7 cases (19.4%), and pancreaticobiliary maljunction in 1 case (2.8%). For patients with congenital bile duct dilation and Biliary cancer, the positive cells of proliferating cell nuclear antigen were increased significantly (P < 0.05). Different types in pancreaticobiliary ductal union investigated in this study may provide clues for pathogenesis and clinical treatment of pancreaticobiliary maljunction.