Osteosarcoma is a bone tumor that can occur in any bone. It most commonly occurs in the long bones of the extremities near metaphyseal growth plates.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%).
In about 75% of cases, patients with osteosarcoma are between 15–25 years of age. Male are more frequently affected than female (ration 1.5:1). Osteosarcoma rarely occurs in patients younger than 6 years or older than 60 years. Tumours observed in older age usually develop secondary to Paget's disease, radiation or dedifferentiated chondrosarcomas. Mifamurtide is used after a patient has had surgery to remove the tumor and together with chemotherapy to kill remaining cancer cells to reduce the risk of cancer recurrence. Also, the option to have rotationplasty after the tumor is taken out exists.