Suppressed Immune System

Cancer cells of non-Hodgkin lymphoma develop from cells of the immune system. As a result, challenges or weakness of the immune system may increase the risk of non-Hodgkin lymphoma. Examples include:

• Chronic infections such as Epstein-Barr (causes mononucleosis), HIV, helicobacter pylori (causes peptic ulcers) or HTLV.
• Autoimmune diseases such as Sjogren syndrome, rheumatoid arthritis, celiac disease, or systemic lupus erythematosus
• Medications that suppress the immune system such as those used to prevent organ transplant rejection

Occupational or Environmental Exposures

Exposures to certain chemicals or radiation may increase the risk of lymphoma. People who work around pesticides, fertilizers, and certain chemical solvents have a greater chance of developing non-Hodgkins lymphoma than people who do not.

People who have survived nuclear accidents or explosions are also at an increased risk. Fallout from nuclear radiation stays in the environment for years. However, radiation exposure from medical and dental x-rays is not associated with an increased risk.

Family History

People who have a parent with non-Hodgkins lymphoma may have an increased risk of developing it. This is especially true if the family member had lymphoma at an early age.

Smoking

Smoking introduces a variety of harmful chemicals into the body that can affect the DNA of cells. The lymph also help carry the chemicals out of the body. The risk of lymphoma increases with the number of cigarettes smoked and years as a smoker.