Understanding different types of bone cancer

At Atlantic Endocrinology & Diabetes Center we know that bone cancer is relatively rare, accounting for 1% of all cancer cases in the United States.

Quite often, bone cancer is the result of metastasis. This means that cancer from elsewhere has spread to the bone. These cancers show the original cancerous cells and not those associated with bone cancer. In these cases, the cancer is treated by following the original course of treatment for the initial tumor.

But there are also primary cancers of the bone. This means that the cancer starts in the bone. Primary bone cancer is not common. Only 2 of every 1000 cancers diagnosed in the US each year are primary bone cancer. Bones are composed of:

Osteoid tissue (hard or compact)
Cartilaginous tissue (tough, flexible)
Fibrous tissue (threadlike)
Bone marrow (soft, spongy tissue in the center of most bones)

The type of bone cancer depends on where in the bone it starts.

There are two main types of bone cancer. In adults, cancers that form in the organs and spread to the bones, or metastasize, are the most common and are called secondary bone cancers. Primary bone cancers, also called bone sarcomas, develop in the bones and often spread to other areas.

The primary forms of bone cancer from most common to least common include:

Osteosarcomas are tumors of the bone and are the most common form of bone cancer. Osteosarcomas are usually diagnosed in young people, but they do occur in older adults. These tumors often form in the arms, legs, or pelvis.
Ewing tumor (Ewing sarcoma) is the second most common bone cancer in young people and third most common overall. These bone tumors often form in the hip, ribs, shoulder blades, spine, and legs.
Chondrosarcoma forms in cartilage cells. The risk for this type of cancer increases with age and is rare in patients under 20. Chondrosarcomas are graded by severity from one to three.
High-grade undifferentiated pleomorphic sarcoma (UPS) is another rare form of cancer that is often found in the soft tissues but can also occur in the bones, especially the legs, arms, and abdomen. It can also occur in areas of the body where radiation was received. UPS is most common in middle-aged and elderly adults.
Fibrosarcoma is also rare in bones, occurring mostly in the soft tissues. It usually forms in the legs, arms, and jaw and is most common among adults 50 and older.

Chordoma is a rare bone tumor that most often forms at the bottom of the spine or the base of the skull. It’s commonly diagnosed in older adults.

Giant cell tumor is another primary bone tumor often occurring in young people between age 20 and 30. However, the tumor is noncancerous, or benign, and usually forms near the joints of long bones, such as the shins and thighs.

The secondary types of bone cancer

There are several types of secondary bone cancer. These cancers are slightly different from metastasized bone cancer because they don’t form in the bone cells. Instead, they form in the blood or immune cells found in bone marrow.

The secondary types of bone cancer include:

Multiple myeloma forms in a type of immune cells called plasma cells that are in the bone marrow. This type of bone cancer may develop as a single tumor but is usually found in several bones.
Leukemia forms in the blood cells of bone marrow. There are many different types of leukemia. It can happen to people of all ages but is the most common cancer among young people.
Non-Hodgkin lymphoma develops in the white blood cells of areas in the body that have lymph tissue. Primary non-Hodgkin lymphoma of the bone is a very rare type of lymphoma that forms in the bones.

Bone Cancer Risk Factors

Research is increasing regarding what we know about bone cancer. Scientists are learning more about its causes. Following are common risk factors for the disease:

Genetic Disorders – A small number of bone tumors are believed to be the result of genetic mutations:

The Li-Fraumeni Syndrome – A mutation of the p53 tumor suppressor gene makes people much more likely to develop several types of cancer, including breast cancer, brain cancer, osteosarcoma, and other types of sarcoma.
Rothmund-Thomson Syndrome – Children with this syndrome are short, have skeletal problems, and rashes. They also are more likely to develop osteosarcoma.
Multiple Exostoses Syndrome – Patients with this inherited condition that causes many bumps on a person’s bones can have an increased risk of chondrosarcoma.

Radiation – Exposure to large doses of radiation may increase the risk of developing bone cancer. Radioactive materials such as radium and strontium can also cause bone cancer because these minerals build up in bones.