Once the radiation team has determined a course of treatment, the actual radiation therapy process begins using a high energy linear accelerator that rotates around the patient to deliver the radiation dose to their tumor from multiple angles.
During treatment, radiation therapists position the patient using the previously described special immobilization devices and shape each beam with patient specific blocking devices* to exactly replicate the treatment prescription specified by the radiation oncologist during the first two phases of treatment planning.
The patient remains alone in the room during treatment but is closely monitored by the radiation therapist from the control room. Treatment is painless (although side effects can cause pain or discomfort) and can last anywhere from a few minutes to a half an hour.
CancerQuest, in association with The American Cancer Society, has created a documentary about radiation therapy. In this multi-part interactive video, doctors describe what radiation therapy is and how it works, while patients treated with radiation therapy discuss how it impacted them.