Bone cancer (sarcoma) - Causes of bone cancer

Cancer begins with a change in the structure of DNA. DNA provides our cells with a basic set of instructions, such as when to grow and reproduce.

A change in DNA structure is known as a mutation, and it can alter the instructions that control cell growth. This means that cells continue to grow instead of stopping when they should. This causes cells to reproduce in an uncontrollable manner, producing a lump of tissue called a tumour.

Known risk factors

Bone cancer is a poorly understood condition and, as a result, only a small number of known risks have been identified. These include:

• Fast-growing bones – as the majority of cases of bone cancer develop in teenagers it is thought the rapid growth spurt that occurs during puberty may in some way make bone tissue more vulnerable to cancer. Higher rates of bone cancer have also been found in certain breeds of dogs that experience rapid bone growth.
• Previous exposure to high doses of radiation, such as undergoing radiotherapy; however, the increased risk associated with radiotherapy is small.
• Paget’s disease of the bone, which is an uncommon bone condition that causes weakening of the bones. However, less than 1 in 100 people with the condition will develop bone cancer in later life.
• Rare genetic conditions such as Li-Fraumeni syndrome, which affects around 1 in every 142,000 people.
• A history of retinoblastoma. This is a rare type of childhood cancer which develops in the eye. People who have had this condition have an increased risk of developing bone cancer.

Research has also found babies born with an umbilical hernia are three times more likely to develop Ewing’s sarcoma than others.

However, the increased risk is still small as only one in 110,000 children with an umbilical hernia will go on to develop Ewing’s sarcoma.

How does bone cancer spread?

Left untreated,  cancerous cells can spread from the affected area of bone. This can involve an inward spread into the bone marrow (the jelly-like material found inside bones) or outwards into the blood and then usually into the lungs.