Definition of Osteosarcoma:

Osteosarcoma is a cancerous (malignant) bone tumor that usually develops during the period of rapid growth that occurs in adolescence, as a teenager matures into an adult.

Causes, incidence, and risk factors:

Osteosarcoma is the most common cancerous (malignant) bone tumor in youth. The average age at diagnosis is 15. Boys and girls have a similar incidence of this tumor until late adolescence, at which time boys are more commonly affected.

The cause is not known. In some cases, osteosarcoma runs in families, and at least one gene has been linked to increased risk. This gene is also associated with familial retinoblastoma, a cancer of the eye that occurs in children.

Osteosarcoma tends to occur in the bones of the:

• Shin (near the knee)
• Thigh (near the knee)
• Upper arm (near the shoulder)

This cancer occurs most commonly in larger bones and in the area of bone with the fastest growth rate. Osteosarcoma can occur in any bone, however.

Although it is rare, osteosarcoma can occur in adults.

Symptoms:

• Bone fracture (may occur after what seems like a routine movement)
• Bone pain
• Limitation of motion
• Limping (if the tumor is in the leg)
• Pain when lifting (if the tumor is in the arm)
• Tenderness, swelling, or redness at the site of the tumor

Signs and tests:

• Blood tests
• Bone scan to see if the cancer has spread to other bones
• CT scan of the chest to see if the cancer has spread to the lungs
• CT scan of the affected area
• Open biopsy (at time of surgery for diagnosis)
• X-ray of the affected area

Treatment:

Treatment usually starts after a biopsy of the tumor.

Before major surgery to remove the tumor, chemotherapy is usually given. This is strong medication injected into the vein (intravenously) to make the tumor shrink. Chemotherapy also treats any cancer cells that may have spread to other parts of the body.

Surgery is then used to remove any remaining tumor. In most cases, surgery can remove the tumor while sparing the affected limb (this is called limb-salvage surgery). Rarely more radical surgery (such as amputation) may be necessary for a permanent cure.

Common chemotherapy medicines include:

• Cisplatin
• Carboplatin (Paraplatin)
• Cyclophosphamide (Cytoxan)
• Doxorubicin (Adriamycin)
• High-dose methotrexate with leucovorin
• Ifosfamide (Ifex)

Support Groups:

Association of Cancer Online Resources -- www.acor.org

Cure Search (formerly the National Childhood Cancer Foundation) --www.curesearch.org

Expectations (prognosis):

If the tumor has not spread to the lungs (pulmonary metastasis), long-term survival rates are very high. If the cancer has spread to other parts of the body, there is still a good chance of cure with effective treatment.

Complications:

• Effects of chemotherapy (vary for each person and depend on the type of chemotherapy given)
• Limb removal
• Lung metastases

Calling your health care provider:

Call your health care provider if you have bone pain, tenderness, or swelling.