INTRODUCTION: True bone cancer (aka primary bone cancer) affects over 2,000 people in the United States each year. Cancer that originates in the bone - primary bone cancer - is rare. Early diagnosis and treatment of this disease increases the likelihood of survival. Children and young people are more likely than adults to develop cancer of the bones. In the past, amputation was common for bone cancer in an arm or leg.

CAUSE: Most of the time, when people have cancer in their bones, it is caused by cancer that has spread from elsewhere in the body to the bones rather than actual cancer of bone cells.

TYPES: There are more than 100 types of cancer, and each type is named for the organ or tissue in which it begins. Certain types of cancers are particularly likely to spread to the bones. It is important to note that when these other types of cancer spread to the bone, they are still named for the tissue or organ where they arose and are not termed "bone" cancer.

Many different kinds of cancer are able to spread to the bones. The most common kinds of cancer that spread to the bones are lung, breast, prostate, thyroid, as well as kidney.

There are several types of sarcomas of the bone, depending upon the kind of bone tissue where the tumor developed. The most common types of primary bone cancer are osteosarcoma, Ewing's sarcoma, and chondrosarcoma. Other, more rare types include fibrosarcoma, malignant giant cell tumor, and chordoma.

SYMPTOMS: The symptoms of bone malignancy tend to happen slowly and depend on the kind, location, and size of the tumor. Pain is the most frequent sign of bone cancer and doctors often use radiation therapy to shrink tumors to reduce the pressure, pain or other symptoms they may produce.

TREATMENT: Treatment depends on the kind of bone cancer, as well as its location, size and stage. It can involve chemotherapy with multiple drugs as well as radiation therapy and surgery to eliminate the primary tumor.

Treating cancer that has spread to the bones (metastatic cancer) depends on the form of cancer (the tissue where it originated) and the extent of the spread. As with other malignancies, treatment depends on the size, type, location and stage of the cancer, including whether it has metastasized to the lungs or other parts of your body, and your overall health.

Your doctor may suggest using radiation therapy at different times during your cancer treatment and for different reasons, such as before surgery to shrink a cancerous tumor or after surgery to stop the growth of any remaining cancer cells.

A well-coordinated team of doctors - including surgeons, medical oncologists, radiation oncologists, and physical medicine and rehabilitation specialists who are familiar with treatment of sarcomas - is important for increasing the chance you'll be able to have limb-sparing treatment. In some cases, chemotherapy may be the only treatment you need. More often, doctors use it in conjunction with other treatments, such as surgery or radiation, to improve results.

CONCLUSION: In contrast to cancers which have metastasized to the bone, real bone cancers are tumors that originate from the tissues of the bones. These malignancies, called primary bone cancers, are very rare in comparison to those that have spread to the bones.

Pain is the most frequent symptom of bone malignancy, but sometimes a lump on the bone can be felt through the skin. It is very rare to have a true bone cancer, one that arises from cells that make up the bone.

The treatment and prognosis of the disease depends upon a number of factors including the type and extent of the malignancy, the person's age and overall basic health. The disease may be treated with surgery, radiation therapy, chemotherapy, or a combination of them all.