Orthopaedic Oncology

Chondroblastoma is a rare type of benign (noncancerous) tumor that usually develops at the ends of long bones, such as the thighbone and upper arm bone. Although it can affect people of all ages, it most often appears in males younger than 25 years old. Most chondroblastomas are found around the knee at the end of the femur (thighbone) or top of the tibia (shinbone). They are also commonly found at the shoulder at the top of the humerus (upper arm bone). This type of chondroblastoma is often referred to as a "Codman's tumor." Sometimes, chondroblastomas are found in the pelvis, hip, or heel. Pain is the most common symptom of chondroblastoma. Because these tumors are typically found near joints, patients often see doctors because of joint pain. A chondroblastoma is usually small and contained within the bone, so patients do not normally see or feel a mass.

Enchondroma is one type of benign (noncancerous) cartilage tumor that appears on the inside of the bone. These tumors usually begin and grow in childhood, then stop growing but remain present throughout adulthood. They are often found in patients between 10 and 20 years of age. These tumors are very common and often occur in the small bones of the hand and feet. They are the most common tumor of the hand. They also occur in the long bones of the upper arm and thigh.

Fibrous dysplasia is a chronic condition of the skeleton where a portion of a bone develops abnormally. The condition begins before birth. It is caused by a gene mutation that affects the cells that produce bone. Although the abnormal bone forms before birth, its presence is often not discovered until childhood, adolescence, or even adulthood. Fibrous dysplasia accounts for approximately 7% of all benign bone tumors. Any bone may be affected. The most common bones involved are the thighbone, shinbone, ribs, skull, upper arm bone, and pelvis. The cause of the gene mutation is not known. It is not inherited or passed on to the children of affected patients. No dietary or environmental cause is known. It occurs equally among males and females of all races.

Giant cell tumor of bone (GCT) is a rare, aggressive non-cancerous (benign) tumor. It generally occurs in adults between the ages of 20 and 40 years. Giant cell tumor of bone is very rarely seen in children or in adults older than 65 years of age. Giant cell tumors occur in approximately one person per million per year. Giant cell tumors of bone most frequently occur around the knee joint in the lower end of the thighbone (femur) or the upper end of the shinbone (tibia). Other common locations include the wrist (lower end of the lower arm bone), the hip (upper end of the thighbone), the shoulder (upper end of the upper arm bone), and lower back (connection of the spine and pelvis). If not treated, these tumors will continue to grow and destroy bone. Surgery has proven to be the most effective treatment for giant cell tumors.

The hemangiomas that occur in bones typically occur in the skull or spine and are most common in people who are 50 to 70 years of age. Capillary and cavernous types are the most common hemangiomas found in bone. They can grow on the surface or deeper into the center canal of a bone. Because they typically do not cause symptoms, these tumors are often found by chance when an x-ray image is taken for other purposes.

Considered a non-cancerous aggressive tumor, Osteoblastomas are larger in size and grow progressively. Osteoblastomas are rare tumors and constitute about 1% of excised primary bone tumors. These tumors have a higher chance of coming back after they are removed.

An osteochondroma is a benign (noncancerous) tumor that develops during childhood or adolescence. It is an abnormal growth that forms on the surface of a bone near the growth plate. An osteochondroma is an outgrowth of the growth plate and is made up of both bone and cartilage. As a child grows, an osteochondroma may grow larger, as well. Once a child has reached skeletal maturity, the osteochondroma typically stops growing, too. In most cases of osteochondroma, no treatment is required other than regular monitoring of the tumor to identify any changes or complications. Because many osteochondromas do not cause any discomfort or other symptoms, they are often discovered by accident when an x-ray is done for an unrelated reason.