Risk factors for soft tissue sarcoma
A risk factor is something that increases the risk of developing cancer. It could be a behaviour, substance or condition. Most cancers are the result of many risk factors. But sometimes soft tissue sarcoma develops in people who don’t have any of the risk factors described below.
Soft tissue sarcoma can develop at any age, but it occurs most often in people older than 50 years of age.
Risk factors are generally listed in order from most to least important. But in most cases, it is impossible to rank them with absolute certainty.
Risk factors
There is convincing evidence that the following factors increase your risk for soft tissue sarcoma.
Radiation therapy
People who receive radiation therapy as treatment for another cancer have a higher risk of developing soft tissue sarcoma. This is particularly true for people who received radiation therapy for Hodgkin lymphoma, non-Hodgkin lymphoma or breast cancer. Soft tissue sarcoma often develops in the area of the body that was treated with radiation. The average time between coming into contact with radiation and a diagnosis of soft tissue sarcoma is 10 years.
Less than 5% of sarcomas are caused by radiation therapy. The benefit of using radiation therapy to treat cancer outweighs the increased risk of developing soft tissue sarcoma.
Genetic conditions
The following rare inherited conditions increase the risk of developing soft tissue sarcoma.
Retinoblastoma is a cancerous tumour that develops in the retina (the membrane at the back of the eye). It occurs mostly in children.
Werner syndrome causes people to age very rapidly after puberty.
Li-Fraumeni syndrome is associated with an increased risk of developing several types of cancer, including soft tissue sarcoma.
Neurofibromatosis type 1 (also known as von Recklinghausen disease) affects the nervous system. It is a condition that causes tumours to form in nerve tissues in and under the skin. People with neurofibromatosis type 1 have a higher risk of developing certain cancers, including soft tissue sarcoma.
Gardner syndrome causes large numbers of polyps in the colon, along with tumours in the bone and soft tissues.
Chronic lymphedema
Lymphedema is a buildup of fluid in body tissues. Long-term, or chronic, lymphedema can cause lymphangiosarcoma (also called Stewart-Treves syndrome). This is a rare type of soft tissue sarcoma that develops in lymph vessels
Viral infections
The following viral infections increase your risk of developing soft tissue sarcoma.
Kaposi sarcoma herpes virus (KSHV) is also called human herpes virus 8 (HHV-8) or Kaposi sarcoma-associated herpes. This virus can cause a rare type of sarcoma called Kaposi sarcoma (KS).
Human immunodeficiency virus (HIV) increases the risk of developing KS and soft tissue sarcoma.
Vinyl chloride
Vinyl chloride is used in the plastics industry to make polyvinyl chloride (PVC), which is used in many products. Coming into contact with vinyl chloride at work increases the risk of developing angiosarcoma of the liver, a type of soft tissue sarcoma.
Thorium dioxide
Thorium dioxide (Thorotrast) is a radioactive solution that was used as a contrast medium in the 1950s to improve x-ray images of the blood vessels and arteries, nasal passages and sinus cavities. Thorium dioxide was injected into a vein and it collected in the liver, spleen and bone marrow. People who were exposed to thorium dioxide have a greater risk of developing angiosarcoma of the liver, which is a type of soft tissue sarcoma. Higher doses of thorium dioxide increase the risk. The cancer may develop as many as 45 years after exposure.
Possible risk factors
The following factors have been linked with soft tissue sarcoma, but there is not enough evidence to show for sure that they are risk factors. More research is needed to clarify the role of these factors for soft tissue sarcoma.
- previous chemotherapy treatment
- personal history of cancer
- coming into contact with dioxin at work
No link to soft tissue sarcoma
Significant evidence shows no link between soft tissue sarcoma and injury or trauma.
Questions to ask your healthcare team
To make the decisions that are right for you, ask your healthcare team questions about risks.