External Beam Radiation Therapy (EBRT)
External radiation (or external beam radiation) is the most common type of radiation therapy used for cancer treatment. A machine is used to aim high-energy rays (or beams) from outside the body into the tumor. Radiation technology allows the very careful delivery of external beam radiation therapy. These machines focus the radiation on the exact location where it needs to be, so that normal tissues are affected as little as possible
This type of radiation therapy uses electrons directed at the entire surface of the body. This type of radiation goes into the outer layers of the skin, but does not go deeper into tissues and organs below the skin.