What is bone cancer?
- Bone cancer is a malignant (cancerous) tumor of the bone that destroys normal bone tissue. Not all bone tumors are malignant. In fact, benign (noncancerous) bone tumors are more common than malignant ones. Both malignant and benign bone tumors may grow and compress healthy bone tissue, but benign tumors do not spread, do not destroy bone tissue, and are rarely a threat to life.
Signs and symptoms
- Pain is the most common symptom of bone cancer, but not all bone cancers cause pain (1). Persistent or unusual pain or swelling in or near a bone can be caused by cancer or by other conditions. It is important to see a doctor to determine the cause.
- Although bone cancer does not have a clearly defined cause, researchers have identified several factors that increase the likelihood of developing these tumors. Osteosarcoma occurs more frequently in people who have had high-dose external radiation therapy or treatment with certain anticancer drugs; children seem to be particularly susceptible. A small number of bone cancers are due to heredity. For example, children who have had hereditary retinoblastoma (an uncommon cancer of the eye) are at a higher risk of developing osteosarcoma, particularly if they are treated with radiation. Additionally, people who have hereditary defects of bones and people with metal implants, which doctors sometimes use to repair fractures, are more likely to develop osteosarcoma . Ewing sarcoma is not strongly associated with any heredity cancer syndromes, congenital childhood diseases, or previous radiation exposure.
- To help diagnose bone cancer, the doctor asks about the patient’s personal and family medical history. The doctor also performs a physical examination and may order laboratory and other diagnostic tests.
- X-rays, which can show the location, size, and shape of a bone tumor. If x-rays suggest that an abnormal area may be cancer, the doctor is likely to recommend special imaging tests. Even if x-rays suggest that an abnormal area is benign, the doctor may want to do further tests, especially if the patient is experiencing unusual or persistent pain.
- Biopsy (removal of a tissue sample from the bone tumor) to determine whether cancer is present. The surgeon may perform a needle biopsy or an incisional biopsy. During a needle biopsy, the surgeon makes a small hole in the bone and removes a sample of tissue from the tumor with a needle-like instrument. In an incisional biopsy, the surgeon cuts into the tumor and removes a sample of tissue. Biopsies are best done by an orthopedic oncologist (a doctor experienced in the treatment of bone cancer). A pathologist (a doctor who identifies disease by studying cells and tissues under a microscope) examines the tissue to determine whether it is cancerous.
- Blood tests to determine the level of an enzyme called alkaline phosphatase. A large amount of this enzyme is present in the blood when the cells that form bone tissue are very active—when children are growing, when a broken bone is mending, or when a disease or tumor causes production of abnormal bone tissue. Because high levels of alkaline phosphatase are normal in growing children and adolescents, this test is not a completely reliable indicator of bone cancer.
How often does bone cancer occur?
- Primary bone cancer is rare. It accounts for much less than 1 percent of all cancers. About 2,300 new cases of primary bone cancer are diagnosed in the United States each year.
Different types of bone cancer are more likely to occur in certain populations:
Osteosarcoma occurs most commonly between ages 10 and 19. However, people over age 40 who have other conditions, such as Paget disease (a benign condition characterized by abnormal development of new bone cells), are at increased risk of developing this cancer.
Chondrosarcoma occurs mainly in older adults (over age 40). The risk increases with advancing age. This disease rarely occurs in children and adolescents.
ESFTs occur most often in children and adolescents under 19 years of age. Boys are affected more often than girls. These tumors are extremely rare in African American children.
- Surgery is the usual treatment for bone cancer. The surgeon removes the entire tumor with negative margins (no cancer cells are found at the edge or border of the tissue removed during surgery). The surgeon may also use special surgical techniques to minimize the amount of healthy tissue removed with the tumor.
- Chemotherapy is the use of anticancer drugs to kill cancer cells. Patients who have bone cancer usually receive a combination of anticancer drugs. However, chemotherapy is not currently used to treat chondrosarcoma.
- Radiation therapy, also called radiotherapy, involves the use of high-energy x-rays to kill cancer cells. This treatment may be used in combination with surgery. It is often used to treat chondrosarcoma, which cannot be treated with chemotherapy, as well as ESFTs.It may also be used for patients who refuse surgery.
- Cryosurgery is the use of liquid nitrogen to freeze and kill cancer cells. This technique can sometimes be used instead of conventional surgery to destroy the tumor.