A case of a primary hepatic so-called adenosarcoma with heterotopic ossification: possibly of biliary adenofibroma origin.

We present an autopsy case of a "so-called adenosarcoma with ossification of the liver" in a 63-year-old man. Macroscopically, the well-circumscribed tumor with portal vein invasion was observed in the right lobe of the liver. The cut surface of the tumor had a solid and microcystic appearance. Microscopically, the tumor was characterized by a benign epithelial component and a malignant mesenchymal component. We believe the presence of biliary adenofibroma-like areas and the von Meyenburg complexes suggests that the tumor is possibly associated with a biliary adenofibroma. In addition, the present tumor was unique in that it showed scattered heterotopic ossification. Immunohistochemical study showed that the mesenchymal atypical spindle cells had characteristics of undifferentiated mesenchymal cells. This is the first report of a primary hepatic so-called adenosarcoma.