Synchronous Double Bile Duct Cancers with Distinct Genetic Features.

A 69-year-old man was referred to our hospital because of appetite loss. Imaging showed a nodular tumor in the perihilar bile duct and a second flat lesion in the distal bile duct. Right hepatopancreaticoduodenectomy was performed, and the histopathological findings demonstrated that the perihilar and distal lesions were moderately and poorly differentiated adenocarcinoma, respectively, and anatomically separated. Furthermore, the resected specimens showed no pancreaticobiliary maljunction. Histological and TP53 gene analyses in a rare case of synchronous double bile duct cancers suggest that there are various genetic pathways through which bile duct cancer develops, highlighting the complexity of its pathogenesis.