Osteosarcoma and malignant fibrous histiocytoma (MFH) of the bone are forms of bone cancer. Osteosarcoma usually starts in osteoblasts, which are a type of bone cell that become new bone tissue. Osteosarcoma is most common in teenagers. It is the most common type of bone cancer and, according to the National Cancer Institute, some 450 children and young adults are diagnosed with this form of cancer each year in the United States.
Having past treatment with radiation can increase the risk of osteosarcoma. Other risk factors for osteosarcoma include treatment with anticancer drugs called alkylating agents, having a certain change in the retinoblastoma gene, and having certain conditions including Paget disease, Diamond-Blackfan anemia and Werner syndrome.
Malignant fibrous histiocytoma (MFH) of bone is a rare tumor of the bone. It is treated like osteosarcoma.
Source: National Cancer Institute