Hilar cholangiocarcinoma accompanied by pancreaticobiliary maljunction without bile duct dilatation 20 years after cholecystectomy: report of a case.

Pancreaticobiliary maljunction (PBM) is associated with the occurrence of biliary cancer due to pancreatobiliary reflux. From the perspective of carcinogenesis, the treatment for PBM is controversial. We herein report a case of hilar cholangiocarcinoma 20 years after the occurrence of gallbladder cancer. A 75-year-old man was referred to our hospital regarding an obstructive jaundice and bile duct tumor. A cholecystectomy was performed for cholelithiasis on this patient 20 years ago, and cancer in situ was detected. Computed tomography (CT) and endoscopic retrograde cholangiopancreatography (ERCP) revealed a tumor of the portal hepatic region and PBM without dilatation of the bile duct. Adenocarcinoma was detected from bile cytology, and we diagnosed hilar cholangiocarcinoma. Despite the biliary decompression, jaundice was prolonged and the patient passed away. Our case suggests that not only cholecystectomy but also biliary diversion is needed for PBM regardless of the existence of bile duct dilatation.