The exact causes of primary bone cancer are not known. There are certain things that can affect the chances of developing primary bone cancer. These are called risk factors. Having a risk factor does not mean you will get bone cancer. People without risk factors can also develop bone cancer.
Many bone cancers affect teenagers and young people. This might mean that bone cancer may be related to changes that happen in growing bones.
Research into possible causes of bone cancer is going on all the time but for most people it is not clear why they develop bone cancer.
Some non-cancerous bone conditions can increase your risk of developing bone cancer.
Some conditions can increase the risk of osteosarcoma. These include the following:
- Paget’s disease of the bone - which causes painful and deformed bones.
- Fibrous dysplasia - which is a condition where bone is replaced with scar-like tissue. It most commonly affects teenagers and young adults. It can cause swelling and painful, deformed bones.
Some rare conditions can increase the risk of developing chondrosarcoma:
- Osteochondroma (or chondroma)
Osteochondromas are non-cancerous growths that develop on the bones. Rarely, these growths can develop into chondrosarcoma.
- Hereditary multiple exostoses (HME)
HME is also called hereditary multiple osteochondroma (HMO). This is a rare genetic condition that causes bony lumps to grow on the surface of bones. It often starts in childhood and is usually inherited.
- Ollier’s disease and Maffucci’s syndrome
Ollier’s disease and Maffucci’s syndrome are rare conditions that cause non-cancerous growths in cartilage close to the bone. They often start in childhood, but they are not inherited.
Most bone cancers are not caused by a gene that you can inherit. But some genetic conditions increase the risk of developing bone cancer.
People who have Li-Fraumeni syndrome have an increased risk of developing osteosarcoma. Li-Fraumeni syndrome is an inherited condition that increases the risk of several cancers.
Children who have retinoblastoma have an increased risk of developing osteosarcoma. Retinoblastoma is a rare type of eye cancer caused by an inherited gene change.
Children who are born with an umbilical hernia have an increased risk of developing Ewing sarcoma. The risk is still very small.
A hernia is a bulge caused by an internal part of the body pushing through a weakness in the muscle or tissue wall. An umbilical hernia is a hernia in the belly button.
Sometimes people find out they have primary bone cancer after an injury to their bone. They may think the injury caused the cancer to develop.
There is no clear evidence that an injury to a bone can cause bone cancer. But it may draw attention to a bone cancer that is already there.