Factors



A risk factor is anything that increases your chance of getting a disease such as cancer. Different cancers have different risk factors. For example, exposing skin to strong sunlight is a risk factor for skin cancer. Smoking is a risk factor for cancers of the lung, mouth, larynx, bladder, kidney, and several other organs. But having a risk factor, or even several, does not mean that you will get the disease. Most people with bone cancers do not have any apparent risk factors.
Inherited genes: A very small number of bone cancers (especially osteosarcomas) appear to be hereditary. Children with certain rare inherited cancer syndromes have an increased risk of developing osteosarcoma. The Li-Fraumeni syndrome makes people much more likely to develop several types of cancer, including breast cancer, brain cancer, osteosarcoma, and other types of sarcoma. Most of those cases are caused by a mutation of the p53 tumor suppressor gene. Another syndrome that includes bone cancer is the Rothmund-Thompson syndrome. Children with this syndrome are short, have skeletal problems, and rashes. They also are more likely to develop osteosarcoma.
Retinoblastoma is a rare eye cancer of children. Between 6% and 10% of cases are due to an inherited tendency to develop this cancer. Children with this inherited form of retinoblastoma also have an increased risk for developing osteosarcoma. This is because of an abnormal mutation of the retinoblastoma gene that predisposes them to developing cancer. Also, radiation therapy for treating children with retinoblastoma increases their risk for osteosarcoma in the bones of the skull.
Finally, there are families with several members that have developed osteosarcoma without inherited changes in any of the known genes. The gene defects that may cause cancers in these families haven’t been discovered yet.
Paget disease: Paget disease is a benign (non-cancerous) but precancerous condition that affects one or more bones. It results in formation of abnormal bone tissue and is mostly a disease of people older than 50. Affected bones are heavy and thick, yet weaker than normal bones and more likely to fracture (break). Usually this condition is not life threatening. Bone sarcomas (usually osteosarcoma) develop in about 5% to 10% of severe cases of Paget disease, usually when many bones are affected.
Multiple exostoses: This is an inherited condition sometimes called multiple osteochondromas that causes many bumps on a person's bones. These can be painful and cause bones to deform and/or fracture. Although they feel hard, multiple exostoses are made mostly of cartilage. Patients with multiple osteochondromas have an increased risk (about 1% to 2%) for chondrosarcomas.
Radiation: Bone exposure to radiation may also increase the risk of developing bone cancer. A typical x-ray of a bone is not dangerous, but exposure to large doses of radiation (for example, radiation therapy to treat another cancer), even though necessary to treat the original cancer, does pose a risk. Being treated at a younger age and/or being treated with higher doses of radiation (usually over 60 Gy) increases the risk of developing bone cancer. Exposure to radioactive materials such as radium and strontium may cause bone cancer because these minerals build up in bones. Nonionizing radiation, such as microwaves, electromagnetic fields from power lines, cellular phones, and household appliances, does not increase bone cancer risk.
Bone marrow transplantation: Osteosarcoma has been reported in a few patients who have undergone bone marrow (stem cell) transplantation.
Injuries: People have wondered whether injury to a bone can cause cancer, but this has never been proven. Many people with bone cancer remember having hurt that part of their bone. Most doctors believe that this did not cause the cancer, but that the cancer caused them to remember the incident, or that the injury drew their attention to that bone and caused them to notice a mass that had already been present for some time.

   

 

  
     

2007 Dreamers