Of the several forms of primary bone and joint cancer (ICD-9 170.0–170.9), osteosarcoma is the most common primary bone cancer, accounting for about 35% of all cases. Occurring more frequently in males, osteosarcoma is found mostly in people 10–30 years old and rarely during middle age. About 10% of cases develop in people 60 years old and older. Other, rare forms of primary bone cancer include chondrosarcoma (cancer of cartilage cells), Ewing’s tumor (cancer of the bone cavity), chordoma (cancer of the skull base and spinal bones), and malignant fibrous histiocytoma and fibrosarcoma (cancer of the connective tissues). The 5-year survival rate can be as high as 80%, but the prognosis for people with primary bone cancer varies greatly, depending on the specific type of cancer and the stage at which it is diagnosed (ACS, 2000e; NCI, 2002i).

Risk factors for bone cancer are exposure to ionizing radiation, particularly at an early age or at high doses; a history of bone disorders, such as Paget’s disease; and the presence of multiple exostoses (overgrowths of bone tissue), multiple osteochondromas (benign bone tumors formed by bone and cartilage), multiple enchondromas (benign cartilage tumors), and some genetic factors (such as mutation of the p53 tumor-suppressor gene) (ACS, 2000e; NCI, 2002i).