Cytologic features of fibrolamellar carcinoma with mucin production: a rare variant of combined hepatocellular-cholangiocarcinoma.

Fibrolamellar carcinoma (FC) is an uncommon tumor that usually arises in non-cirrhotic livers of adolescents or young adults. It differs clinically from hepatocellular carcinoma in its better prognosis and lack of gender predilection. Cytologically, the tumor is composed of large polygonal cells with abundant cytoplasm, pleomorphic nuclei, and prominent large nucleoli. A variant of FC with mucinous differentiation has been previously described. These tumors have been regarded as combined hepatocellular cholangiocarcinomas. Herein, we report the case of a 44-year-old Asian female with a large liver mass present for approximately two years. Core needle biopsy with imprint cytology demonstrated FC with areas of intracellular mucin. To our knowledge, cytological features of this rare tumor have not been described before.