Sarcomas of fat and bone: a case report.

Osteosarcomas are the most common primary malignant bone tumors and are classified by the WHO into several intramedullary and surface subtypes. One of these is the rare parosteal osteosarcoma. Liposarcomas are the second most common soft tissue sarcoma and are classified into several types ranging from intermediate to high grade tumors. In one of our recent patients we found an unusual combination of a parosteal osteosarcoma and a large fatty component, which fluorescence-in-situ-hybridization revealed as liposarcoma. Radiologists, pathologists, and surgeons should consider the possibility of bone and soft tissue malignancies consisting of different components, as this may be of paramount importance for oncologically complete resection.