A case of primary mucinous carcinoma of the distal bile duct with extensive perineural invasion

Abstract

An 81-year-old man presented with stenosis in the distal bile duct that was diagnosed using endoscopic retrograde cholangiopancreatography. Bile duct biopsy detected a carcinoma in situ (BilIN-3). A computed tomography scan revealed wall thickening of the distal bile duct, which showed a contrast effect. The contrast effect of the biliary duct wall was observed up to the right hepatic artery branch. The patient was diagnosed with distal bile duct cancer. A subtotal stomach preserving pancreatoduodenectomy was performed. Histopathological examination revealed a well differentiated mucinous adenocarcinoma, and the tumor was accompanied by extensive perineural invasion. Mucinous adenocarcinoma of the common bile duct is rare in literature. Our case provides a characterization of extensive perineural invasion.