A case of carcinoma in situ of extrahepatic bile duct concomitant with IPMC

Abstract

We herein report a case of carcinoma in situ of bile duct concomitant with Intraductal papillary-mucinous carcinoma (IPMC). An 81-year-old female was referred to our hospital after the detection of a pancreatic tumor. Computed tomography (CT) and endoscopic ultrasonography (EUS) showed a cystic lesion with a solid component at the pancreas head. Endoscopic retrograde cholangiopancreatography (ERCP) showed the extrusion of mucin through a patulous ampullary orifice and the presence of mucin in the pancreatic duct. Mucin was also present in the bile duct, which was thought to have regurgitated from the pancreatic duct. She was diagnosed with IPMC due to the presence of the solid component and underwent pancreaticoduodenectomy. The pathological findings showed IPMC with micro-invasion as well as bile duct carcinoma in situ, which is difficult to diagnose in preoperative examinations. Carcinoma in situ of bile duct concomitant with IPMC is extremely rare. This case also suggests that a relationship exists between pancreatobiliary reflux and carcinogenesis in the bile duct.