Combined hepatocellular/cholangiocellular carcinoma with sarcomatoid features: genetic analysis for histogenesis.

The histogenesis of sarcomatoid transformation in hepatocellular carcinomas (HCCs) and cholangiocellular carcinomas (CCCs) remains unclear. In the current case, microsatellite loss of heterozygosity (LOH) assay and mutational analysis of the p53 gene with immunohistochemical examination were performed to investigate the histogenesis of each component. The tumor was composed of two parts: one part comprised poorly differentiated HCC (HCC portion), while the other part included undifferentiated, sarcomatoid HCC and CCC (combined portion).