Bone cancer is a malignant tumor in the bone that destroys normal bone tissue. Cancer that begins in the bone is very rare. More often, cancer metastasizes, or spreads to bone from another part of the body, such as the breast or lung. Fewer than 2,500 new cases of primary bone cancer are diagnosed in the United States each year – less than 1% of all cancers found.
Three types of cancer may begin in bone tissue: osteosarcoma, which occurs most often in late childhood or adolescence, and often presents in the knee and upper arm; chondrosarcoma, which begins in cartilage and usually appears in the pelvis, upper leg, or shoulder in people older than age 40; and Ewing’s sarcoma, which occurs most often in the spine, pelvis, or legs and arms of children and teens and is more common in boys than girls, according to the National Cancer Institute.
Pain is the primary symptom of bone cancer. Persistent or unusual swelling in or near a bone may suggest the need for screening for bone cancer. If warranted, a bone biopsy may be performed to look for cancerous tissue.
Modern imaging studies help identify specific types and stages of bone cancer. For example, a computed tomography (CT) scan setting may be adjusted to study a “bone window” that focuses on the high contrast between bone and soft tissues to better study bone tissue. PET/CT scan with sodium fluoride F18 injection (NaF) scans the entire skeletal system and produces images that may be used to detect abnormal bone growth or other symptoms associated with tumors.
Surgery, amputation, chemotherapy, and radiation therapy, or a combination of these treatments, may be recommended for bone cancer. In limb-sparing surgery, bone grafting may be needed, or an internal device called an endoprosthesis may be implanted.
High-resolution imaging and newer surgical techniques coupled with tumor treatment prior to surgery have dramatically reduced the rates of amputation in recent years, and clinical trials are constantly seeking ways to evaluate and treat bone cancer. Targeted therapies that use small molecules to “starve” pathways that cancer cells use to survive and multiply, as well as proton therapies that deliver high radiation doses directly into a tumor while sparing nearby tissues and organs may be available at some treatment centers or through clinical trials. Researchers are exploring pemetrexed, a drug originally approved to treat lung cancer by preventing malignant cells from using folate in the body to promote cancer cell growth, for its potential in improving outcomes in patients with advanced bone cancer.
For more information, visit the National Cancer Institute.