Osteosarcoma
Osteosarcomas are primarily malignant bone tumors found predominantly in the iliac bones. Most commonly, the proximal parts of the tibia, humerus and distal parts of the femur are affected.
The age of onset is between 10 and 25 years. Tumor cells produce immature osteoid and bone tissue that rapidly metastasizes. About 50% of osteosarcomas are located at the knee joint.