Intrahepatic cholangiocarcinoma arising in congenital hepatic fibrosis: report of an autopsy case.

We report an autopsy case of a 60-year-old woman who had congenital hepatic fibrosis with intrahepatic cholangiocarcinoma. A white nodular lesion with a surrounding vague gray area was detected in the right lobe of the liver. Microscopically, most of the nodular lesion was a poorly-differentiated adenocarcinoma. In the surrounding gray area, small bile ducts and bile ductules showed prominent epithelial overgrowth, some of which was composed of dysplasia and well-differentiated adenocarcinoma. The background liver showed the characteristic features of congenital hepatic fibrosis. Immunohistochemically, biliary oncofetal markers (mucin core protein 1 and carcinoembryonic antigen) were more frequently and extensively expressed in poorly-differentiated than well-differentiated adenocarcinoma. This is the 4th reported case of intrahepatic cholangiocarcinoma arising in congenital hepatic fibrosis and suggests that malignant transformation via dysplasia occurs in the abnormal intrahepatic biliary tree of older congenital hepatic fibrosis patients.