External Beam Radiotherapy
About external beam radiotherapy
External beam radiation is the most widely used type of radiation therapy, and it most often uses photon beams. The radiation comes from a machine outside the body and is focused on the cancer. It’s a lot like getting an x-ray, but for longer. This type of radiation is most often given by machines called linear accelerators (linacs).
External beam radiation can be used to treat large areas of the body. It also can treat more than one area, such as the main tumor and nearby lymph nodes. External radiation is usually given daily over several weeks. It’s given in an outpatient clinic or treatment center, so you don’t have to stay in the hospital. The radiation is aimed at the cancer, but in most cases it affects the normal tissue it passes through on its way into and out of the body.