Osteosarcoma is a kind of bone cancer. It most often starts in a leg bone (either the femur or the tibia) near the knee or in the upper arm bone (the humerus) near the shoulder. Osteosarcoma can metastasize (spread) to other parts of the body, most often to the lungs or other bones.
Your child or teenager may have a dull aching pain in the bone or joint around the site of the osteosarcoma. The pain can awaken him or her from sleep. Often, there is a firm swelling or lump in the area of the pain. This swelling is caused by a tumor growing inside the bone.
If the cancer is in a leg bone, your child or teenager may limp. Also, the muscles in the arm or leg that has the osteosarcoma may look smaller than the muscles in the opposite arm or leg. Sometimes, the bone can break in the area of the tumor, because the tumor weakens the bone.
Osteosarcoma is not a common cancer. Only about 400 cases occur in the United States each year. Osteosarcoma is, however, the most common bone cancer in children and teenagers. It most often starts between 10 and 20 years of age and more commonly in males. Osteosarcoma has no known cause.
Physical exam: The doctor will check for general signs of health as well as examine the place around the swelling, lump or break. The doctor will also ask about your child’s or teenager’s health history and any previous health conditions or medical treatments.
X-ray: If your child or teenager has signs of an osteosarcoma, your doctor will order X-rays. If there is a tumor, it will usually show up on the X-ray.
MRI and CT: The doctor may also order an MRI scan, a CT scan (also called a CAT scan), or both. MRI scans take pictures that help the doctor see if the tumor has destroyed any of the bone, and a CT scan is useful to look at the belly to see if the disease has spread. Before a CT scan, your child or teenager might be given a kind of dye, either with a shot, or to be swallowed. The dye helps the organs or tissues show up more clearly on the scan.
Biopsy: A biopsy is important because malignant (cancerous) tumors and some infections can look like osteosarcoma on an X-ray. For the biopsy, a doctor with training in the treatment of bone cancer takes a piece of the tumor from the bone, sometimes with a needle, sometimes through an incision. This piece of tissue is looked at under a microscope to see if the tumor is an osteosarcoma.
Other tests: If your child or teenager has osteosarcoma, more tests will be done to see if the cancer has spread to the lungs or other organs. A bone scan will see if the cancer has spread to other bones. Before the bone scan, your child or teenager will be given a small shot of a radioactive substance that helps cancer cells show up on the scan. Other tests may also be needed.
Osteosarcoma is treated with chemotherapy and surgery. For chemotherapy, your child or teenager will be given medicines that kill the main tumor and any tumor cells that have moved to other parts of the body. Chemotherapy treatment is normally recommended for about 6 months for cancer that has not spread. This treatment is usually started before surgery to kill the tumor or make it smaller. This makes surgery easier. If chemotherapy is not likely to alter the course of the cancer, surgery or amputation may be the first part of the treatment plan.
Almost everyone who has this cancer can have "limb-sparing" surgery. In this surgery, the tumor is removed along with the area of bone that it grew in. Sometimes an entire joint, like the knee joint, is removed. Then the missing bone is replaced with an artificial metal bone called an endoprosthesis (say: “end-o-pross-thee-sis”).
After the surgery, your child or teenager will have more chemotherapy.
Today, about 3 out of 4 people who have osteosarcoma can be cured if the cancer has not spread to other parts of the body. Almost everyone who is treated with limb-sparing surgery ends up with that arm or leg working well.
To make the leg or arm strong, and so that it works well again, your child or teenager will have to do special exercises for several months after the surgery. If amputation is necessary, your child or teenager will have intense rehabilitation for some time. There are many new prosthetic treatments now available that can help your child or teen regain movement and independence.
After the chemotherapy is over, your child or teenager will:
Osteosarcoma: A Multidisciplinary Approach to Diagnosis and Treatment by JC Wittig, J Bickels, D Priebat, J Jelinek, K Kellar-Graney, B Shmookler, MM Malawer (American Family Physician March 15, 2002, http://www.aafp.org/afp/20020315/1123.html)
Written by familydoctor.org editorial staff