[A case of combined hepatocellular-cholangiocarcinoma with sarcomatous transformation and second primary colon cancer].

Abstract Combined hepatocellular-cholangiocarcinoma is a rare form of primary liver cancer, featuring both hepatocellular and biliary epithelial differentiations. An intrahepatic tumor may be considered as a metastatic lesion. It has been suggested in the literature that the likelihood of metastasis in the cirrhotic liver is lower than that in the non-cirrhotic liver. A rare case of combined hepatocellular-cholangiocarcinoma and second primary colon adenocarcinoma in a 67-year-old male patient with liver cirrhosis is presented. Histologically, the intrahepatic mass was composed of a spindle cell sarcomatous component; a hepatocellular carcinoma component; and a cholangiocarcinoma component. There were focal transitional regions among the different components. Immunohistochemically, the cholangiocarcinoma component of the intrahepatic mass showed positive reactions for CK-7 but negative reactions for CK-20. The adenocarcinoma of the colon showed positive reactions for CK-20 but negative reactions for CK-7.