External Beam Radiation Therapy
The goal of radiation therapy is to get a high enough dose of radiation to the tumor while sparing the surrounding healthy tissue from damage. During external beam radiation therapy, a beam of radiation is directed through the skin to a tumor and the immediate surrounding area in order to destroy the main tumor and any nearby cancer cells. It is a painless procedure. The machine used to deliver external beam radiation therapy is called a linear accelerator, sometimes called a "linac." It produces a beam of high-energy X-rays or electrons. Using sophisticated treatment planning software, your radiation oncology treatment team plans the size and shape of the beam, as well as how it is directed at your body, to effectively treat your tumor while sparing the normal tissue surrounding it.