Osteosarcoma is a type of bone cancer. It starts in immature bone cells that normally form new bone tissue. It destroys local tissue and weakens the bone. Very rarely, it presents in the soft tissues, outside of a bone.
Osteosarcoma most often begins in the thigh or shin bones. The second most common place to begin is in the upper arm bone, close to the shoulder, but it can develop in any bone in the body. It affects about 400 children and adolescents under the age of 20 each year, and it most commonly affects adolescents during the growth spurt.
Signs and Symptoms of Osteosarcoma
Symptoms can vary depending on the bone in which the cancer develops. Symptoms may include:
- Pain in the bone or joint that gets worse over time
- A painless swelling or a noticeable mass in the arm or leg
- A broken bone that occurs without injury or with minimal injury
- Stiffness or swelling of joints (uncommon)
- Back pain or loss of bowel or bladder control related to a tumor in the pelvis or at the base of the spine. This is very rarely the first sign that a child has this disease.