Histopathology of carcinomas of the liver in mice fed perthane.

B6C3F1 female mice fed an average dose of 3,000 ppm of perthane for 2 years developed a highly significant incidence of hepatocellular carcinomas of the liver. Male mice fed 2,500 ppm perthane had a slight increase of carcinoma of the liver. Some of the carcinomas were well-differentiated; however, most were poorly differentiated or undifferentiated. Perthane-treated mice also had well and poorly differentiated cholangiocarcinomas and carcinosarcomas, neoplasms not seen in control mice.