context: Bone tumors grow when cells in the bone divide without control, forming a mass of tissue. Most bone tumors are benign, which means they are not cancer and do not spread to other areas of the body. But they may still weaken bone and lead to broken bones or cause other problems. Bone cancer destroys normal bone tissue. It may start in the bone or spread from other parts of the body (called metastasis). Benign tumors are more common than tumors caused by cancer. These are a few common types of benign bone tumors: Osteochondroma is the most common benign bone tumor. It is more common in people under age 20. Giant cell tumor is a benign tumor, typically in the leg (malignant types of this tumor are uncommon). Osteoid osteoma is a benign bone tumor, often found in long bones, that happens commonly in the early 20s. Osteoblastoma is a rare, benign tumor that grows in the spine and long bones, mostly in young adults. Enchondroma usually appears in bones of the hands and feet. It often has no symptoms. It is the most common type of hand tumor. Cancer that's in your bones has most often come from cancer elsewhere in your body. For example, if lung cancer has spread to your bones, that's secondary bone cancer. Any cancer that moves from one part of the body to another is called metastatic cancer. Cancers that commonly spread to bone include: Breast cancer Prostate cancer Lung cancer Primary bone cancer, or bone sarcoma, is a cancerous tumor that starts in the bone. The cause is not certain, but heredity may play a role. Radiation therapy or cancer drugs may raise your chances of getting this type of cancer. As with all cancer, if primary bone cancer spreads to other places in your body, it's called metastatic cancer. These are some of the most common types of primary bone cancer: Osteosarcoma is most common around the knee and upper arm. Most of the time, it is found in teens and young adults. There is an adult form of this tumor that is usually seen in people with Paget's disease of bone. Ewing's sarcoma also is seen in younger people between the ages of 5 and 20. The ribs, pelvis, leg, and upper arm are the most common sites. It usually shows up in bone, but it can also start in soft tissue around bones. Chondrosarcoma happens most often in people between 40 and 70. The hip, pelvis, leg, arm, and shoulder are common sites of this cancer, which begins in cartilage cells. Although almost always found in bone, multiple myelomais not a primary bone cancer. It is a bone marrow cancer. Bone marrow is the soft tissue inside bones. You may have no symptoms of a bone tumor, whether it's cancer or not. This is common. Your doctor may find a tumor when looking at an X-ray of another problem, such as a sprain. But symptoms may include pain that: Is in the area of the tumor Is dull or achy May get worse with activity Wakes you at night Trauma does not cause a bone tumor, but a bone that is weakened by a tumor may break more easily. This can cause severe pain. Other symptoms related to bone tumors may include: Fevers Night sweats Swelling around a bone Limping If you think you might have a bone tumor, see your doctor right way. Your doctor will ask you questions about your symptoms and medical history and do a physical exam. You may need blood and imaging tests. To confirm a diagnosis, your doctor may remove tissue with a needle or through a cut and have it examined under a microscope for signs of cancer. This is called a biopsy. Cancerous bone tumors need more aggressive treatment. Benign tumors are watched or may be treated with medication. Your doctor may remove benign tumors that are more likely to spread or become cancer. In some cases, tumors come back, even after treatment. Tumors caused by bone cancer, whether primary or metastatic, may need the attention of several cancer specialists. Treatment depends on how far it has spread, called its stage. Cancer cells confined to the bone tumor and surrounding area are at a localized stage. Bone cancers that spread to or from other areas of the body are more serious and a cure is more difficult. Cancers of the bone are most often removed with surgery. These are the common types of treatment for bone cancer: Limb salvage surgery removes the part of the bone with cancer. Nearby muscles, tendons, and other tissues are not removed. A metallic implant replaces the portion of bone that was removed. Amputation may be done if a tumor is large or extends to nerves and blood vessels. You may get a prosthetic limb after amputation. Radiation therapy kills cancer cells and shrinks tumors with high-dose X-rays. It is often used in combination with surgery and may be used before or after surgery. Chemotherapy kills tumor cells with cancer drugs. Chemotherapy may be given before surgery, after surgery, or for metastatic disease. Your doctor may recommend that you join a clinical trial. They test new treatments. Regardless of your type of treatment, you will need regular follow-up visits with your doctor.