Osteogenic sarcoma is a type of cancer that affects the bone. About 900 new patients, primarily between the ages of 10 and 25, are diagnosed each year. About 60 percent of osteogenic sarcomas occur in the legs and knees. However, it can affect other bones, such as the shoulders and the jaw, where it is harder to treat.
To this day, researchers aren’t sure what causes osteogenic sarcoma. Some think that repeated trauma to a specific area causes increased presence of osteoid tissue to repair the area, leading to malignancy. Another theory is that the cause is genetic, being linked with the same gene that causes retinoblastoma. Osteogenic sarcoma may also result from continued irradiation exposure from treatment of other cancers.
People with osteogenic sarcoma often complain of a bruising or swelling of the area, with a feeling of a bump. Pain is constant, but becomes worse at night. The bone in question is very weak, and can break more easily. The bone affected also will be more difficult to move.
X-rays, bone scans, magnetic resonance imaging ( MRI) and computed tomography (CT) scans are all used to diagnose osteogenic sarcoma. A biopsy, or removal of a small portion of the questionable tissue, can confirm the existence of osteogenic sarcoma. The cancer is then staged to determine how far it has spread and how much it has advanced. If detected early enough, it may not have metastasized and may be prevalent only in the surrounding tissue. However, in many cases (due to the symptoms associated with bone breaks and common injuries), the cancer may not be diagnosed early and may have metastasized to the lungs. If this has happened, it will be more difficult to treat, and the survival rate diminishes.
Treatment for osteogenic sarcoma is a three-step process:
Neoadjuvant chemotherapy, administering chemotherapy before surgery, may be recommended to reduce the tumor’s size before it is surgically removed. Treatment usually involves drugs such as methotrexate, cisplatin, doxorubicin, etoposide, ifosfamide and pegylated interferon alfa 2b.
Surgery involves either complete amputation (in rare cases) or a procedure known as limb-salvage surgery. Limb-salvage involves removing the affected tissue and part of the surrounding area. A follow-up treatment may involve endoprosthesis, where the lost bone tissue is replaced by either a bone graft, or a piece of plastic-metal alloy. After limb-salvage surgery, patients are required to undergo a recovery regimen that lasts from six to 12 months (amputees require longer recovery time, and must cope with the psychological effects of amputation), usually involving a CPM (continuous motion machine) that bends and straightens the limb.
Post-surgery chemotherapy is administered. After surgery, a biopsy is performed to determine the size of the tumor. If less than 10 percent is present, then the surgery is considered to be a success and a lighter treatment of methotrexate is administered. However, if more than 10 percent is present within the body then a more concentrated dose of chemotherapy is administered.
Treatment for osteogenic sarcoma can last anywhere from 26 weeks to two years, depending on how early or advanced the cancer was at diagnosis, and how effective the treatment is.
Osteogenic sarcoma has one of the lower survival rates among young adults and children afflicted with cancer. The five-year survival rate is about 65 percent to 70 percent.