Pelioid hepatocellular carcinoma in an adult Eurasian badger (Meles meles)

A mass was identified within the left lateral lobe of the liver of a 10-year-old Eurasian badger (Meles meles). The mass was friable and multilobulated, with blood-filled spaces between the lobules. Microscopically, the lesion consisted of sheets and trabeculae of neoplastic hepatocytes often forming cystic spaces containing erythrocytes, fibrin and necrotic debris. The histological appearance was consistent with hepatocellular carcinoma (HCC). Immunohistochemically, the neoplastic cells expressed cytokeratin 18 but not von Willebrand factor. Multiple intranuclear (amphophilic or acidophilic) inclusion bodies were observed in hepatocytes at the junction between the tumour and normal hepatic tissue. HCCs have also been reported in other domestic and wild animals. As hepadnavirus infection has been associated with HCC in woodchucks, further histochemical and transmission electron microscopical studies were performed; however, these demonstrated that the inclusions consisted of lipid droplets and not viral particles. To our knowledge, this is the first report of a naturally occurring HCC in a Eurasian badger.