Risk Factors

A risk factor is anything that increases a person’s chance of developing cancer. Some risk factors can be controlled, such as smoking, and some cannot be controlled, such as age and family history. Although risk factors can influence the development of cancer, most do not directly cause cancer. Some people with several risk factors never develop cancer, while others with no known risk factors do. However, knowing your risk factors and communicating them to your doctor may help you make more informed lifestyle and health-care choices.

The exact cause of NHL is not known, but the following factors may raise a person’s risk of developing NHL:

Age. The risk of NHL increases with age. The most common types occur most often in people in their 60s and 70s.

Gender. Men are more likely to develop NHL than women.

Infections. Some types of NHL are associated with specific infections. For example, MALT lymphoma is thought to be caused by a bacterium known as Helicobacter pylori. If this lymphoma is diagnosed very early, the lymphoma will sometimes go away if the bacterium is eliminated from the stomach with antibiotics. Other types of MALT lymphoma, including those affecting the lungs and the tear glands, may also be caused by infections.

Virus exposure. Viruses are thought to be involved in causing some types of NHL. For example, EBV is associated with some types of NHL, including Burkitt lymphoma, and lymphomas occurring after solid organ transplantations. However, the virus is probably not the only factor, so people who have had mono do not necessarily have an increased risk of developing NHL in the future. Other viruses have also been identified as being important in causing other rare types of lymphoma.

Immune deficiency disorders. Immune system disorders, such as HIV/AIDS, increase the risk of NHL, especially the aggressive B-cell lymphomas.

Autoimmune disorders. People with autoimmune disorders, such as rheumatoid arthritis and Sjögren syndrome, are at an increased risk for developing certain types of NHL. Also, some drugs used to treat autoimmune disorders may increase the risk of NHL.

Organ transplantation. Organ transplant recipients are at a higher risk for NHL because of the immune-suppressing drugs that must be taken.

Previous cancer treatment. Previous treatment with certain drugs for other types of cancer may increase the risk of NHL.

Chemical exposure. Exposure to certain chemicals, such as pesticides and petrochemicals, may increase the risk of NHL.