What is a risk factor?

A risk factor is anything that may increase your chance of having a disease. Risk factors for certain cancers might include smoking, diet, family history, sun exposure, or many other things. The exact cause of someone’s cancer may not be known. But some risk factors can make it more likely for a person to have cancer.

Things you should know about risk factors for cancer:

• Risk factors can increase your risk. But they don't always cause the disease. 

• Some people with one or more risk factors never get cancer. Other people with cancer have no known risk factors.

• Some risk factors are very well known. But experts are studying risk factors for many types of cancer.

• Some risk factors are not in your control. This includes your family history, age, and sex. But others might be things you can change. Knowing about risk factors can help you make choices that might help lower your cancer risk.

Who is at risk for non-Hodgkin lymphoma?

Risk factors for non-Hodgkin lymphoma include:

• Age. The risk of non-Hodgkin lymphoma goes up as you get older. Still, some types of non-Hodgkin lymphoma are more common in younger people.

• Sex. More men than women get non-Hodgkin lymphoma. But certain types are more common in women.

• Epstein-Barr virus (EBV) infection. EBV is the virus that causes mono (mononucleosis). People who have been infected with this virus may have a higher risk of non-Hodgkin lymphoma. Still, many people are infected with EBV, but few of them get non-Hodgkin lymphoma.

• Certain other infections. Infection with certain other viruses and bacteria can raise your risk for some types of non-Hodgkin lymphoma. This includes infections with the hepatitis C virus, the HTLV-1 virus, and a type of bacteria known as H. pylori ( Helicobacter pylori). 

• A weak immune system. A weakened immune system puts you at higher risk for non-Hodgkin lymphoma. For instance, people who are infected with HIV have an increased risk. The same is true of people who have had organ transplants and take medicine to suppress their immune system.

• Past cancer treatment. If you've been treated for cancer in the past and had certain types of chemotherapy or radiation therapy, you may have a slightly higher risk for non-Hodgkin lymphoma.

• Autoimmune disorders. Diseases like rheumatoid arthritis, Sjogren disease, systemic lupus erythematosus (SLE or lupus), and celiac disease put you at higher risk.

• Certain chemicals. Working with certain chemicals, such as benzene, insecticides, and some herbicides, may increase your risk.

• Breast implants. In rare cases, breast implants can lead to lymphoma in the breast.

What are your risk factors?

Talk with your healthcare provider about your risk factors for non-Hodgkin lymphoma. Ask if there are things you can do to help lower your risk. Some of the risk factors for non-Hodgkin lymphoma can’t be changed, but some can. Staying at a healthy weight; eating lots of vegetables, fruits, and whole grains; and exercising regularly can also have many benefits, including lowering your cancer risk.

There are no screening tests to look for non-Hodgkin lymphoma if you don’t have symptoms. But you should know about possible symptoms of non-Hodgkin lymphoma. This is even more important if you have known risk factors for it. See a healthcare provider if you have symptoms like swollen lymph nodes, tiredness (fatigue), night sweats, fever, or unexplained weight loss that don’t go away after a few weeks.