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External Beam Radiation Therapy Treatments


When you have external beam radiation therapy treatment each session is painless - like getting an X-ray.

Radiation is directed at your tumor from a machine called a linear accelerator.

Unlike surgery, which is an invasive process, external beam radiation is noninvasive.

One of the benefits of radiation therapy is that it usually is given as a series of outpatient treatments - meaning you don't have to stay in the hospital.

You may not need to miss work or have a recuperation period that may follow other treatments.

About the Treatments

  • Treatments usually are scheduled five days a week - Monday through Friday - and continue for one to 10 weeks.
  • The number of treatments you'll need depends on the size, location and type of your cancer; the intent of treatment; your general health; and other medical treatments you may be receiving.
  • The radiation therapist will give your treatment following your radiation oncologist's instructions. It will take 10 to 20 minutes to position you for treatment and set up the equipment. If an immobilization device was made during simulation, it will be used during every treatment to ensure you're in the exact position every session.
  • Once you are positioned correctly, the therapist will leave the room and go into the control room next door to closely monitor you on a television screen while giving radiation.

    The treatment room has a microphone and camera so you can talk with the therapist if you have concerns. He or she will also be able to see you. We can stop at any time if you're feeling sick or uncomfortable.
  • The therapist may move the treatment machine and table to target the radiation beam to the tumor's exact area. While the machine may make noises during treatment that sound like clicking or knocking, the therapist is in complete control of the machine at all times.
  • The radiation therapy team carefully aims radiation to reduce the dose to normal tissue surrounding the tumor. Still, radiation will affect some healthy cells. Time between daily treatments allows your healthy cells to repair much of the radiation effect, while cancer cells are not as likely to survive.
  • Sometimes treatment may be interrupted for a day or more if you develop side effects. These missed treatments may be made up by adding treatments at the end.

    Try to arrive on time and not miss appointments. Time spent in the treatment room may vary depending on the type of radiation, but it generally ranges from 10-20 minutes. Most patients are treated on an outpatient basis and many can continue with normal daily activities.
  • Your radiation oncologist monitors your treatment and may alter your radiation dose based on his or her observations. Also, your doctor may order blood tests, X-rays and other tests to see how your body is responding to treatment.

Weekly Status Checks

During radiation therapy, your radiation oncologist and nurse will see you regularly to follow your progress, evaluate whether you are having any side effects, recommend treatments for those side effects (such as medication) and address your concerns.

As treatment progresses, your doctor may change your schedule or treatment plan depending on your response or reaction to therapy.

Weekly Treatment Films

During your course of treatment, we will regularly verify correct positions of the treatment beams with images from the planning scan. These images - called port films or portal verification - do not evaluate the tumor but are an important quality assurance check.