A combined hepatocellular/cholangiocellular carcinoma with sarcomatoid features

A case of primary liver cancer showing combined hepatocellular and cholangiocellular features and an associated pseudosarcomatous (schwannomatous) component is presented. Histologically, compact microtrabecular and glandular patterns in a dense fibrous stroma were recognized. The latter showed transition towards spindle cell sarcomatous growth in several areas of both the primary and the lymph-node metastasis. Glandular areas expressed acidic mucins and AE1-reactive keratins; albumin mRNA was detected by in situ hybridization in both trabecular and glandular areas. Vimentin and S-100 protein were mostly expressed in the pseudosarcomatous areas. Both the morphological patterns and the phenotypic features indicate that divergent differentiation along both epithelial and mesenchymal lineages took place in this rare primary liver tumor.