Osteosarcoma is the most common primary malignancy of bone. It arises in bone during periods of rapid growth and primarily affects adolescents and young adults.The most common sites include the femur (42%), with 75% of tumors in the distal femur; tibia (19%), with 80% of tumors in the proximal tibia; and humerus (10%), with 90% of tumors in the proximal humerus. Other locations of note include the skull or jaw (8%) and pelvis (8%).
Osteosarcoma is rarely diagnosed in patients younger than 5 years (about 1% of cases). In children aged 5-9 years, the annual incidence is 2.6 cases per million population. In children aged 10-14 years, the annual incidence is 8.3 cases. In adolescents aged 15-19 years, the annual incidence is 8.9 cases.Standard therapy is a combination of limb-salvage orthopedic surgery when possible (or amputation in some cases) and a combination of high-dose methotrexate with leucovorin rescue, intra-arterial cisplatin, adriamycin, ifosfamide with mesna, BCD (bleomycin, cyclophosphamide, dactinomycin), etoposide, and muramyl tripeptide. Rotationplasty may be used. Ifosfamide can be used as an adjuvant treatment if the necrosis rate is low.