Combined hepatocellular and mucinous carcinoma.

A rare autopsy case of combined liver cell and bile duct carcinoma (CLBC) occurring in a 51-year-old male with alcoholic liver cirrhosis is presented. Histologically, while the primary lesion was solely composed of well differentiated hepatocellular carcinoma (HCC), intrahepatic metastases consisted of a variable admixture of HCC and cholangiocarcinoma (CC) with excessive mucin production. Interestingly, the tumor cell cluster showing a trabecular growth pattern produced both bile and mucin, thus converting from HCC to mucinous CC. It is concluded that this liver malignancy is principally HCC with a marked tendency to transform into CC. The importance of the findings, especially the simultaneous production of bile and mucin within the same cell cluster, is emphasized in terms of the classification of CLBCs.