[Cholangiocarcinoma with bile duct adenoma and hamartoma-like lesion in the bile duct].

A 76-year-old man presented with fever of unknown origin. Diagnostic imaging showed a liver tumor measuring 3cm in maximum dimension. The tumor was subsequently resected, and histopathology showed a moderately differentiated adenocarcinoma. This showed a number of bile ductules with variable amounts of stroma, well circumscribed but not encapsulated, so the lesion was diagnosed as a cholangiocarcinoma. Within the tumor there was also a cholangiolocarcinoma-like lesion. In addition, cystically dilated ductules resembling bile duct hamartoma and bile duct adenoma adjacent to the tumor were found, but with no area of transition among them. In the Glisson's capsule around the tumor, there was also a bile duct hamartoma.