Radiation therapy is the use of high-energy rays to kill cancer cells. Radiation was once used very commonly for treating children with non-Hodgkin lymphoma. But as doctors have developed more effective chemotherapy treatments, the use of radiation therapy has become much more limited.

Radiation focused on a cancer from a source outside the body is called external beam radiation. This is the type of radiation therapy most often used to treat non-Hodgkin lymphoma. The treatment is much like getting an x-ray, but the radiation is more intense. The procedure itself is painless. Before the treatments start, the radiation team takes careful measurements to determine the correct angles for aiming the radiation beams and the proper dose of radiation. Each treatment lasts only a few minutes, although the setup time -- getting your child into place for treatment -- usually takes longer. Most often, radiation treatments are given 5 days a week for several weeks.

There are a few instances in which radiation therapy may be used.

• Sometimes radiation is used along with chemotherapy, such as in patients where the lymphoma has reached the brain or spinal cord.

• It may be used as a form of urgent treatment in children with symptoms caused by large tumors in the chest.

• It may be used as part of treatment for children receiving a bone marrow or peripheral blood stem cell transplant.

• It can also be used to ease (palliate) symptoms caused by lymphoma in internal organs, such when it is causing pain because it is pressing on nerves.

Possible risks and side effects of radiation therapy

Short-term side effects of radiation therapy may include mild, sunburn-like skin problems or fatigue. Radiation of the abdomen may cause nausea, vomiting, or diarrhea. Often these effects go away after a short while.

Possible long-term side effects of radiation therapy in children can be more serious, and may occur after many years.

• Chest radiation therapy may damage the lungs or heart, which could reduce these organs' ability to function. In the long term, radiation may increase the risk of lung cancer (especially in smokers) and of breast cancer, though it is not common. Girls will have a higher chance of developing breast cancer in later years.

• Side effects of brain radiation therapy usually become most serious 1 or 2 years after treatment and may include headaches and problems such as memory loss, personality changes, and trouble learning at school.

• Radiation to other parts of the body may slow their growth or increase the risks for certain other cancers, such as those of muscle or bone (called sarcomas) or of the digestive tract.

Because of these possible long-term effects, doctors try to avoid using radiation therapy in children or limiting the doses used whenever possible.

Last Medical Review: 07/08/2009
Last Revised: 07/08/2009