Primary Bone Cancer: Introduction
What is cancer?
Cancer is when cells in the body change and grow out of control. Your body is made up of tiny building blocks called cells. Normal cells grow when your body needs them, and die when your body does not need them any longer.
Cancer is made up of abnormal cells that grow even though your body doesn't need them. In most cancers, the abnormal cells grow to form a lump or mass called a tumor. If cancer cells are in the body long enough, they can grow into (invade) nearby areas. They can even spread to other parts of the body (metastasis).
What is primary bone cancer?
Primary bone cancer is cancer that begins in your bones. It is also sometimes just called bone cancer.
Primary bone cancer is different from secondary, or metastatic, bone cancer, which starts in another part of the body and later spreads to the bones. If the cancer starts somewhere else, it is not called bone cancer. Instead, it keeps the name of the organ from which it spread. Lung cancer that spreads to the bone is still called lung cancer, for example. Many types of cancer can spread to bone.
Leukemia is a different type of cancer that begins in the soft, inner parts of certain bones (bone marrow). It is considered a blood cancer, not a bone cancer.
Primary bone cancers are quite rare. They are more common in children and teens than in adults.
Primary bone tumors can be noncancerous (benign) or cancerous (malignant). Benign tumors don’t spread and are not usually life-threatening. They are generally removed with surgery. Cancerous tumors can spread and can be life-threatening.
Understanding the bones
The bones have a number of different functions in the body:
Some bones help protect our vital organs.
Some bones, such as those in the arms and legs, make a framework for our muscles that helps us move.
Bones also act as a place in the body to store minerals such as calcium.
The 2 main types of cells in our bones help them stay strong and keep their shape:
Osteoblasts are cells that help build up bones by forming the bone matrix. This is the connective tissue and minerals, such as calcium, that give bone its strength.
Osteoclasts are cells that break down bone matrix to prevent too much of it from building up. This helps bones keep their proper shape.
By depositing or removing minerals from the bones, osteoblasts and osteoclasts also help control the levels of these minerals in the blood.
Like other tissues of the body, bones have many other kinds of living cells as well. Any of these cells can develop into cancer.
What types of cancer can start in the bones?
Primary bone cancers are called sarcomas. Sarcomas can grow from bone, cartilage, fatty tissue, fibrous tissue, muscle, or nerve tissue.
These are the main types of bone cancer:/p>
Osteosarcoma. This is the most common primary bone cancer. It usually starts in bones of the arms or legs near where new bone is made. Most people who get this cancer are between ages 10 and 30. But it can occur at any age. It tends to be more common in males than in females. Most tumors occur near the knee, pelvis, or shoulder, but they can occur in any bone.
Chondrosarcoma. This is the second most common primary bone cancer. This cancer most often occurs in older adults, and it is equally common in men and women. The cancer develops in cartilage cells and is most common around the hip bones. But it can occur in any bone and can also affect the ribs.
Ewing sarcoma. This cancer affects mainly children and teenagers. It is also referred to as Ewing tumor. Most Ewing tumors start in bone, but they can also occur in the soft tissues of the limbs, such as in muscles. Ewing sarcoma usually occurs in the thigh bone, pelvis, or chest wall, but can occur in any bone.
Fibrosarcoma and malignant fibrous histiocytoma. These cancers are most commonly found in soft tissues such as ligaments, tendons, fat, and muscle around bone, but they can develop in bones. They usually affect the legs, arms, or jaw. Older adults are most likely to get these types of cancers.
Giant cell tumors of bone. These tumors are almost always benign. But in rare cases they can be cancerous. They most often occur around the knee or shoulder and sometimes other bones. They don't often spread to other sites, but tend to return after they are surgically removed. With each recurrence, the chances of the cancer spreading to other parts of the body increases. There is also soft tissue tumor called giant cell tumor, which is not related to this bone tumor.
Chordoma. This type of tumor usually grows at the base of the skull or in the spine. Less often, it occurs in other parts of the spine. It is most common in adults ages 30 and older. It is about twice as common in men than in women.
Talk with your healthcare provider
If you have questions about bone cancer, talk with your healthcare provider. Your healthcare provider can help you understand more about this cancer.
March 21, 2017
Alteri, Rick, MD,Levin, Mark, MD