Pathophysiology and treatment strategy for congenital biliary dilatation and pancreaticobiliary maljunction

Abstract

Pancreaticobiliary maljunction is a congenital malformation in which the pancreatic and bile ducts join anatomically outside the duodenal wall. This malformation is classified into a dilated bile duct type (congenital biliary dilatation) and a non-dilated bile duct type. Pancreaticobiliary maljunction causes pancreatic juice to reflux into the bile duct, causing inflammation, duct dilatation, and the possibility of malignant transformation; therefore, surgery is indicated. Surgical management for congenital biliary dilatation comprises bile duct resection with cholecystectomy followed by biliary reconstruction, and the management for the non-dilated type of pancreaticobiliary maljunction is prophylactic cholecystectomy. Insurance reimbursements have covered laparoscopic surgery for congenital biliary dilatation since 2016 and robot-assisted surgery since 2022 in Japan. Careful long-term postoperative follow-up in both diseases is necessary to identify cholangiocarcinogenesis of the remnant bile duct.