Radiation therapy (also called radiotherapy) is the use of high-energy rays to kill cancer cells. It generally follows breast-sparing surgery. Sometimes, depending on the size of the tumor and other factors, radiation therapy also is used after mastectomy. The radiation destroys breast cancer cells that may remain in the area.
Some women have radiation therapy (alone or with chemotherapy or hormonal therapy) before surgery to destroy cancer cells and shrink tumors. This approach is most often used when the breast tumor is large or cannot easily be removed by surgery.
Doctors use two types of radiation therapy to treat breast cancer:
- External radiation: The radiation comes from a machine. For external radiation therapy, a woman with breast cancer goes to the hospital or clinic. Generally, treatments are scheduled 5 days a week for several weeks.
- Internal radiation (implant radiation): The radiation comes from radioactive material placed in thin plastic tubes put directly in the breast. For implant radiation, the woman stays in the hospital. The implants remain in place for several days. They are removed before the woman goes home.
Some women with breast cancer have both kinds of radiation therapy.
