Introduction

Osteosarcoma is the most common kind of bone cancer. About 900 new cases of osteosarcoma are diagnosed in the United States each year. Almost half of these cases will be in children and teenagers. This disease is slightly more common in males than in females. Osteosarcoma is also known as bone sarcoma.

The cells that form osteosarcoma produce bone matrix (area of the bone that stores calcium and other minerals). But the cancerous tissue of osteosarcoma is not as strong as normal bones. Osteosarcoma often starts near the ends of the long bones, especially around the knee, the part of the thigh bone that is next to the knee, and the part of the lower leg bone that is next to the knee. This cancer can also start in the arm bone near the shoulder, as well as other bones.

The symptoms of bone cancer depend on the size and location of the tumor. Pain is the most common symptom. Tumors arising in or around the joints often cause swelling and tenderness. The tumors can also weaken the bones and interfere with normal movement, thus causing fractures. Other symptoms can include weight loss, fatigue, and anemia (too few red blood cells).

The risk of osteosarcoma is highest during the teenage "growth spurt." The risk of osteosarcoma is also higher in people who were treated with radiation for another cancer, especially if they were treated with a high dose of radiation at a young age. Children and teens with certain kinds of noncancerous bone diseases also have a higher risk of developing osteosarcoma, usually when they are adults.