As is the case with most cancers, scientists don’t know precisely what causes lymphoma. But some factors have been identified that may be related to its development. These risk factors comprise several broad categories, including:

  • increased age
  • infection
  • exposure to certain toxic chemicals
  • compromised immunity
  • genetics 

However, the majority of people who are diagnosed with lymphoma have never been exposed to known risk factors.

Studies continue to explore the causes of Hodgkin lymphoma, including a potential connection between lymphoma and certain environmental factors, herbicides and pesticides, and viruses. While specific factors play a role in increasing the risk for lymphoma, these factors still have not been established as direct causes of the cancer. For instance, Epstein-Barr virus (EBV), though associated with about half of Hodgkin lymphoma cases, is still not considered to be a cause of lymphoma. Similarly, individuals with HIV, as well as those with other rare viruses or bacteria  (human T-lymphocytotropic virus; and the bacteria, Helicobacter pylori) may be at a higher risk for developing NHL due to suppression of the immune system that, under normal circumstances, should identify and eliminate cancer cells.