Non-Hodgkin's lymphoma (NHL) is a form of blood cancer that begins in the lymphocytes, a type of white blood cell. Lymphocytes come in two main varieties, B cells and T cells. Both play an important role in the immune system: B cells protect the body from outside invaders such as viruses, toxins or bacteria, while T cells destroy cancer cells and cells that are infected with a virus.
What are the risk factors for non-Hodgkin's lymphoma?
What causes NHL remains unknown, but the American Cancer Society identifies numerous risk factors that could increase your risk of getting this type of cancer:
- Age: People diagnosed with NHL are usually over 60 years of age, but people of all ages can develop NHL, and certain types of lymphoma are more common in younger people.
- Family history: Research suggests that genes may play a role in NHL.
- Sex: On the whole, more people assigned male at birth develop NHL, though certain subtypes of NHL are more common in people assigned female at birth.
- Race, ethnicity, location: NHL is more common in Caucasians than in African Americans and Asian Americans, at least in the United States. The U.S. and Europe have the highest rates of the disease.
- Exposure to chemicals: Exposure to benzene, an industrial chemical, may be associated with an increased risk of NHL. This is also true of some herbicides (weed killers) and insecticides (insect killers).
- Other cancer treatments: Having been treated with chemotherapy (drugs that kill or slow the growth of cancer cells), radiation therapy (high-dose X-rays)—and especially both—increases the risk of developing NHL later in life.
- Exposure to radiation: Survivors of atomic explosions and nuclear reactor accidents develop cancer in higher rates, including NHL.
- Autoimmune diseases: Rheumatoid arthritis (which affects the joints), lupus (which affects many parts of the body), celiac disease (which damages the small intestine and is triggered by eating gluten) and other autoimmune conditions are associated with an increased risk. An autoimmune condition is when your immune system mistakenly attacks healthy cells and tissues.
- Organ transplant: Such as having a kidney or liver transplant.
- Weakened immune system: Due to an organ transplant, human immunodeficiency virus (HIV) infection or an inherited syndrome that causes a weakened immune system.
- Other health conditions: Hepatitis C (a virus that infects the liver), chlamydia (a sexually transmitted infection), and some types of herpes virus that spread through saliva or by sexual contact are all associated with an increased risk.
Reducing your risk
Studies suggest lifestyle factors may increase a person’s risk of non-Hodgkin’s lymphoma, though more research is needed. These factors include being overweight or obese, and a diet high in meat and saturated fats which are solid at room temperature, like butter. Exercise as you are able, maintaining a healthy weight for you and a diet with plenty of fruits and vegetables may reduce the risk—and have numerous other benefits to overall health.
In general, though, most people who get non-Hodgkin's lymphoma do not have risk factors that can be changed. Whether you have a known risk factor or not, the most important thing to do is see a healthcare provider regularly so that signs and symptoms of NHL—or any disease—can be detected as early as possible.
