About non-Hodgkin lymphoma

What should people know about non-Hodgkin lymphoma?

Lymphoma is a type of cancer that starts in cells called lymphocytes. Lymphocytes are infection-fighting cells that are part of the body's immune system. Lymphocytes may be found in small, oval-shaped organs known as lymph nodes. Groups of lymph nodes are found in the armpits, neck, chest, abdomen and groin. Lymphocytes may also be found in the thymus, spleen, tonsils and bone marrow, and in other parts of the body including the stomach, skin and intestines.

Lymphomas are often divided into two groups based on the way the cells look under a microscope. These groups are Hodgkin lymphoma and non-Hodgkin lymphoma. The information in this fact sheet is about non-Hodgkin lymphoma.

There are many different types of non-Hodgkin lymphoma. Recent advances in classifying the different types should help scientists better understand each type, and what their different risk factors might be.

Each year in New York State, about 2,700 men and over 2,300 women are diagnosed with non-Hodgkin lymphoma. About 650 men and over 500 women in New York die from this disease each year. Non-Hodgkin lymphoma is the fifth most frequently diagnosed cancer, excluding skin cancer, among men and the sixth among women.

Who gets non-Hodgkin lymphoma?

Non-Hodgkin lymphoma occurs more frequently among men than among women. It also occurs more frequently among Whites than among Blacks. Although children can get non-Hodgkin lymphoma, the risk of getting lymphoma increases with age. Approximately 70% of people diagnosed with non-Hodgkin lymphoma are age 50 and over.

What factors increase risk for developing non-Hodgkin lymphoma?

At this time, the causes of non-Hodgkin lymphoma are not well understood. However, scientists agree that certain factors increase a person's risk of developing this disease. These risk factors include:

  • Immune deficiencies. People with depressed immune systems, such as those who have organ transplants or individuals with HIV/AIDS, have an increased risk of getting non-Hodgkin lymphoma.
  • Autoimmune diseases. People with certain types of inflammatory autoimmune diseases, including rheumatoid arthritis, lupus, Sjogren's syndrome and celiac disease, are at greater risk of non-Hodgkin lymphoma.
  • Family History. People with close relatives (parents, brothers/sisters, children) who have had non-Hodgkin lymphoma or other blood cancers (e.g., leukemia, Hodgkin lymphoma) are at increased risk of developing non-Hodgkin lymphoma.

What other risk factors for non-Hodgkin lymphoma are scientists studying?

Many studies have been done of farmers and others exposed to different types of pesticides. Some studies found associations between non-Hodgkin lymphoma and specific types of pesticides, but some did not find associations.

Studies have also been done of people in other occupations. Many of these studies suggest that exposure to certain chemicals, such as some chlorinated solvents, may be associated with getting non-Hodgkin lymphoma.

Viral and bacterial infections may have a role in many cases of non-Hodgkin lymphoma. The Epstein-Barr virus (EBV) (a very common virus that causes infectious mononucleosis, also called "mono"), human T-cell lymphotropic virus 1 and Helicobacter pylori (H. pylori) have each been linked with different rare types of non-Hodgkin lymphoma. Research is under way on the possible association of hepatitis C virus with non-Hodgkin lymphoma.

Other risk factors that are being investigated include exposure to ultraviolet radiation, alcohol consumption, and diet.

Additional research is needed to determine the role, if any, these factors may have in the development of non-Hodgkin lymphoma.

Is the number of people with non-Hodgkin lymphoma increasing?

The incidence of non-Hodgkin lymphoma increased steadily between the 1970s and 1990s. Some, but not all, of this increase was likely due to HIV/AIDS. Since the late 1990s, the incidence of non-Hodgkin lymphoma has leveled off.

What can I do to reduce my chances of getting non-Hodgkin lymphoma?

To help reduce the risk of getting non-Hodgkin lymphoma:

  • Individuals with suppressed immune systems due to HIV/AIDS should talk with their health care provider about treatment and risk for non-Hodgkin lymphoma.
  • Individuals with autoimmune disorders should talk with their health care providers about their risk for getting non-Hodgkin lymphoma.
  • Know your family history and discuss any concerns with your health care provider.

How else can I reduce my risk for cancer?

The following may help reduce the risk of developing cancer:

  • Be aware of workplace health and safety rules and follow them.
  • Limit alcohol use.
  • Choose a healthy diet to achieve and maintain a healthy weight. Eat more vegetables, fruits and whole grains and eat less red and processed (e.g., bacon, sausage, luncheon meat, hot dogs) meats. These actions may reduce the risk of developing many cancers as well as other diseases.
  • Exercise regularly.
  • Do not smoke. If you currently smoke, quit. Avoid exposure to second hand smoke. For more information on quitting smoking, visit the NYS Smoker's Quitline at www.nysmokefree.com or call 1-866-NY-QUITS.
  • Discuss the risks and benefits of medical imaging, such as CT scans, with your health care provider to avoid unnecessary exposure to ionizing radiation. This is particularly important for children.
  • Talk with your health care provider about recommended cancer screenings.

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