Radiation therapy uses high-energy rays or particles to destroy cancer cells. Radiation therapy often plays a limited role in treating non-Hodgkin lymphoma (NHL). This is because most people with NHL have widespread disease when they are diagnosed. However, radiation may be used for NHL:
- as the main treatment for early stage (stage I or sometimes stage II) indolent NHL
- Radiation therapy may be used when NHL is in 1 or 2 lymph node areas in the same part of the body.
- Early stage NHL often responds very well to radiation therapy.
- with chemotherapy to destroy lymphoma cells
- Radiation therapy is often given with chemotherapy – either after or along with chemotherapy – to help destroy lymphoma cells and to reduce the risk of the cancer recurring.
- Radiation therapy to certain areas is usually combined with chemotherapy to treat aggressive lymphomas or for large tumours.
- to relieve pain or to control the symptoms of advanced lymphoma (palliative radiation therapy)
- Radiation can be used to shrink tumours that are pressing on or spreading into other organs or structures. It can also be used to shrink enlarged lymph nodes and relieve symptoms caused by tumours.
The amount of radiation given during treatment, and when and how it is given, will be different for each person.
External beam radiation therapy
Non-Hodgkin lymphoma is usually treated with external beam radiation therapy. A machine directs radiation to the tumour and some of the surrounding tissue. Tumours can often be controlled with low to moderate doses of radiation. Although radiation therapy treatment is usually given each day for 5 days a week, the dose and schedule for the radiation therapy is determined by:
- the type of NHL
- the extent of the disease
- whether the treatment is being given to cure the lymphoma or relieve symptoms (palliate)
Radiation treatments are given to different areas of the body when treating NHL. The radiation field is the part of the body that receives the radiation. Some of the fields where radiation is given for treating lymphoma are:
- involved field – most commonly used
- Radiation is given to only 1 or a few lymph node areas known to contain lymphoma and is used for localized, early stage NHL. Involved field radiation therapy is also called IFRT.
- When radiation is given to a larger area to cover nearby or the next level of lymph node sites, this may be called extended field radiation therapy (EFRT).
- mantle field
- Radiation is given to the lymph nodes in the neck, chest and underarms.
- upper abdominal field
- Radiation is given to lymph nodes around the heart and aorta (para-aortic area) and possibly the spleen (unless it has been removed).
- pelvic field
- Radiation is given to lymph nodes in the pelvis and groin.
- A large amount of bone marrow is also radiated because the hip bones, which contain the most bone marrow, are in this field.
- inverted (upside down) Y field
- Radiation is given to lymph nodes in the upper abdominal and pelvic fields.
Total nodal irradiation is the term used when radiation is given to the lymph nodes in all the fields. It is basically a combination of the mantle and inverted Y fields. This approach may be used for people with widespread, advanced stage disease.
For certain types of lymphoma, such as primary CNS lymphoma, radiation therapy is given to the brain.
Total body irradiation is the term used when low-dose radiation is given to the entire body in preparation for a stem cell transplant.
Each person's situation is unique and the radiation fields may be adjusted depending on the type of lymphoma and the extent of the disease.
See a list of questions to ask your doctor about radiation therapy.