Osteosarcoma

What is osteosarcoma?

Osteosarcoma is the most common form of bone cancer in children. The tumor usually starts in the faster growing ends of the long bones in the arms and legs. It is most common in the bones of the legs near the knee and upper arm near the shoulder, but can occur in any bone.

How does it occur?

The exact cause is not known. The risk is higher if your child has other diseases of the bone. High doses of X-rays may also increase the risk of osteosarcoma. In some cases, osteosarcoma runs in families. Bone tumors usually develop during times of rapid growth, such as adolescence. It is most often seen in children between the ages of 10 and 20, but it can occur in younger children and adults. Osteosarcomas are more common in boys than girls.

What are the symptoms?

Symptoms of osteosarcoma include swelling, bone pain or tenderness. The pain is often worse at night. Tumors in the legs may cause limping, while those in the arms cause pain when lifting. Since the tumor can weaken the bone, bones may break more easily, even during normal activities.

How is it diagnosed?

Your child's healthcare provider will do a physical exam and ask about the history of pain and swelling in your child's bones or joints. Tests might include:

• blood and urine tests
• a bone marrow biopsy, in which a small sample of bone marrow is taken to be checked for cancer cells
• X-rays
• a bone scan, which is a procedure that uses radioactive materials given in a vein (IV) to see if the cancer has spread to other bones
• MRI or CT scan of bones.

How is it treated?

Chemotherapy is usually the first treatment given. Chemotherapy is used to shrink the tumor and to prevent its spread. Radiation treatment is generally not useful.

After chemotherapy, X-rays are done to see how well the tumor has responded. The results will help the doctors decide the type of surgery that will be necessary.

In one type of surgery, called limb-salvage surgery, the cancerous bone and tissue are removed. They are replaced with artificial material or bone from another part of the body. However, the limb-salvage procedure is not always possible. If the tumor has spread, cannot be completely removed, or if the bone would not be strong enough, amputation may be done.

After surgery, sometimes more chemotherapy is needed. Osteosarcoma may spread to the lungs. Your child will have chest CT scans to check for tumors in the lungs.

If the tumor does not spread to the lungs, most children survive. If the cancer has spread to other parts of the body, there is still a good chance of cure with the right treatment.