photon beam radiation therapy

Meaning of photon beam radiation therapy: A type of radiation therapy that uses x-rays or gamma rays that come from a special machine called a linear accelerator (linac).

Definition of photon beam radiation therapy

A type of radiation therapy that uses x-rays or gamma rays that come from a special machine called a linear accelerator (linac). The radiation dose is delivered at the surface of the body and goes into the tumor and through the body. Photon beam radiation therapy is different from proton beam therapy.