A case of juvenile hilar cholangiocarcinoma associated with non-dilated pancreaticobiliary maljunction

Abstract

A 29-year-old male was referred for further examination of epigastric pain. Abdominal CT showed a neoplastic lesion in the hilar bile duct. MRCP showed pancreaticobiliary maljunction (PBM) without dilatation of common bile duct. An extended left hepatectomy with extrahepatic bile duct resection was performed with the diagnosis of hilar cholangiocarcinoma (Bismuth II) associated with non-dilated PBM. Histopathologically, biliary intraepithelial neoplasia (BilIN) lesion was observed in the biliary epithelium continuous to the invasive carcinoma. BilIN spread extensively to the duodenum side of the tumor. High-grade atypical cells (High-grade BilIN) were observed nearby the tumor, suggestively representing carcinogenesis process. This was a rare case of cholangiocarcinoma developed in non-dilated PBM at a young age of less than 30 years.