Radiation therapy is sometimes used to destroy non-Hodgkin lymphoma (NHL) cells that have accumulated in one area of the body. Few NHL cases are treated solely with radiation therapy because lymphoma cells are likely to be widespread throughout the body. But it may be used with other therapies like chemotherapy if you have particularly large masses of lymphoma in one area. It's also used when large lymph nodes are pressing on or invading organs or structures and chemotherapy alone can't control the problem.
During therapy, radiation is directed only to the areas of your body affected by NHL. A machine called a linear accelerator, or linac, delivers beam radiation to targeted area(s) of your body while you lie on a moveable table. Parts of your body not affected by NHL, like the reproductive organs, are shielded to help reduce the treatment's side effects. The procedure itself is painless, though some people may feel uncomfortable remaining in the same position for several minutes during the session.