What is osteosarcoma?
A sarcoma is a type of cancer that develops in connective tissue, such as bone, cartilage, or muscle. A sarcoma that starts in the bones is called an osteosarcoma, or osteogenic sarcoma.
Osteosarcoma most often affects the long bones, such as those in the arms and legs. It usually occurs near the ends of the bones where the fastest growth is taking place (growth plates). The bones and areas most often affected include:
- Femur (thigh bone) near the knee.
- Tibia (shin bone) near the knee.
- Humerus (upper arm bone) near the shoulder.
Other less common locations for osteosarcoma include the pelvis, skull, and jaw.
Who gets osteosarcoma?
Osteosarcoma most often affects pre-teens and teens; the average age at diagnosis is 15. This may be related to the “growth spurt” most children experience at this age.
Osteosarcoma is slightly more common in African-Americans. Before adolescence, it occurs equally in boys and girls. After adolescence, it occurs slightly more often in boys, possibly because of a longer period of skeletal growth.
How common is osteosarcoma?
Osteosarcoma accounts for about 3% of all childhood cancers. It is the third most common cancer in adolescence (after lymphomas and brain tumors); it is the most common primary bone tumor in children. Between 400 and 1,000 new cases of osteosarcoma are diagnosed in the United States each year.
What causes osteosarcoma?
The causes of osteosarcoma are unknown; however, there are some known risk factors, including:
- Rapid bone growth: The risk of osteosarcoma increases during a child’s growth spurts.
- Exposure to radiation: This might have occurred from treatment for another type of cancer. This can take a few or several years to occur.
- Genetic factors: Osteosarcoma is one of several types of rare cancers in young people. This may be related to the retinoblastoma gene, which can be associated with eye cancers in young children or with other tumors in children and young adults in which a mutation of the p53 gene is involved.
What are the symptoms of osteosarcoma?
The most common symptoms of osteosarcoma include:
- Bone pain or tenderness.
- A mass (tumor) that can be felt through the skin.
- Swelling and redness at the site of the tumor.
- Increased pain with lifting (if it affects an arm).
- Limping (if it affects a leg).
- Limited movement (if it affects a joint).
- Broken bone (sometimes after a simple movement).
Diagnosis and Tests
How is osteosarcoma diagnosed?
The doctor will begin with a thorough history and physical examination. The doctor will ask about the child’s symptoms and medical history; for example, whether the child has ever received radiation treatment or whether anyone in the family has certain hereditary conditions.
The doctor might also use certain tests when making the diagnosis. These include:
- Blood tests: These tests can provide information about blood counts and how well organs such as the kidney and liver are working. There is no blood test to detect the presence of a bone tumor.
- X-ray: An X-ray will be done to look for abnormal growths on the bones. Later, a chest X-ray may be done to see if the cancer has spread to the lungs.
- Computed tomography (CT): CT uses computers to combine many X-ray images into cross-sectional views of the inside of the body. This test is used to look for any tumor spread in the lungs.
- Magnetic resonance imaging (MRI): MRI uses a large magnet, radio waves, and a computer to create clear images of the body. This may be ordered for clearer pictures if an X-ray is not normal.
- Bone scan: This test uses a small amount of radioactive material injected into the body to identify bone disorders.
- PET scan: This test uses a special glucose tracer that is concentrated in cancer cells, and shows the areas in the body where the glucose uptake is extra high.
- Biopsy: This is a procedure in which a piece of tissue from the affected area is removed so that it can be studied for cancer cells under a microscope.
Management and Treatment
How is osteosarcoma treated?
The most common forms of treatment for osteosarcoma are:
- Surgery: During surgery, the tumor and some of the healthy tissue around it are cut out of the affected bone. In most cases involving the arm or leg, surgery can be done without amputation. This is called limb-salvage surgery. These procedures may be possible in patients whose cancer has not spread beyond its original site. Sometimes, artificial implants or bone taken from another part of the body can be used to replace the bone that was removed during surgery.
- Chemotherapy: This is the use of drugs to kill cancer cells. Chemotherapy is given before surgery to shrink the tumor. This is called neoadjuvant chemotherapy and often takes about 3 months. Chemotherapy given after surgery to kill any remaining cancer cells is called adjuvant chemotherapy. An oncologist is a doctor who specializes in the treatment of patients who have cancer. An oncologist has expertise not only in prescribing the dose and schedule of these powerful drugs, but also in anticipating and reducing side effects of cancer therapy.
- Radiation therapy: This is important in osteosarcoma involving the spine, sacrum, skull, face, and ribs. For osteosarcoma, a tumor that makes bone, some patients are treated with bone-seeking radiopharmaceuticals (samarium or radium) that are taken up by the bone-forming osteosarcoma cancer cells.
Outlook / Prognosis
What is the outlook for a child who has osteosarcoma?
The outlook depends on many factors, including:
- The size and location of the tumor.
- Whether the cancer has spread to other areas of the body.
- How the child responds to treatment.
- The ability of the immune system to fight the cancer.
Because of improvements in chemotherapy, surgery, radiation, and control of side effects, more children are achieving better results from treatment, experiencing full recovery, and living longer.
When should I call my child’s doctor?
Call your child’s doctor if your child has persistent bone pain, tenderness, or swelling.
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This information is provided by the Cleveland Clinic and is not intended to replace the medical advice of your doctor or healthcare provider. Please consult your healthcare provider for advice about a specific medical condition.
This document was last reviewed on: 03/26/2017