Radiation therapy uses high-energy X-rays or other particles to destroy cancer cells. It only affects cells in the part of the body that is treated. The most common type of radiation treatment is called external-beam radiation therapy, which uses machines called linear accelerators to generate beams of radiation outside of the body and deliver them to cancerous areas of the body. You will not see or feel the radiation as it is being delivered. A doctor who specializes in giving radiation therapy to treat cancer is called a radiation oncologist.
Radiation therapy is most often administered after a lumpectomy to help lower the risk of recurrence in the breast. By combining the modern surgery and radiation therapy, recurrence rates in the breast may now be less than 5 percent in the 10 years following treatment, and survival is often the same as a mastectomy.
The radiation oncologist will discuss personalized treatment options in detail. Radiation therapy for breast cancer can be delivered to the tumor cavity (area where the breast tumor was removed), to the whole breast following breast conservation surgery or to the chest wall/reconstructed breast following mastectomy. Depending on the extent of your particular cancer, you may also receive radiation therapy to the surrounding lymph node regions.
The radiation is delivered on a daily basis, Monday through Friday. The entire radiation course is typically six to seven weeks long, but it may be as short as two to three weeks depending on your particular breast cancer. The typical daily treatment sessions last approximately 10 – 15 minutes.
Side effects are typically limited to gradual changes in skin coloration much like a sunburn reaction, and possibly fatigue. There may be some long-term cosmetic effects of radiation; however, risks to normal organs such as the heart and lungs are very low with modern radiation treatment planning.