Radiotherapy for cancer treatment uses radiation, such as x-rays, gamma rays, electron beams or protons, to kill cancer cells or damage them so they cannot grow or multiply. It is a localised treatment, which means it generally only affects the part of the body where the radiation is targeted. 

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Radiotherapy kills or damages cancer cells in the area being treated. Cancer cells begin to die within days or weeks of treatment starting and continue to die for weeks or months after it finishes. Although the radiation can also damage healthy cells, these can usually repair themselves. 

You should not feel any pain during radiotherapy, but some side effects can cause pain or discomfort. See Managing radiotherapy side effects for more information and ways to prevent or manage side effects.

Watch video on radiotherapy now.

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Questions for your doctor

You may find this checklist helpful when thinking about the questions you want to ask your doctor about your disease and treatment. If your doctor gives you answers that you don’t understand, ask for clarification.

  • Why do I need radiotherapy?
  • What do you expect the radiotherapy to do to the cancer?
  • What kind of radiotherapy treatment will I have?
  • Will it be my only treatment, or will I have other treatments?
  • What side effects should I expect? Will they be long-term or short-term?
  • How long will treatment take?
  • Where will I have treatment? Will I have radiotherapy as an inpatient or outpatient?
  • Will I be radioactive? Will my partner be affected?
  • Is it safe to have sex during radiotherapy treatment?
  • Will treatment interact with any other medicines or vitamins I am taking?
  • When will I know whether the radiotherapy treatment has been successful?
  • How much will treatment cost?
  • Will the cost of my treatment be covered by health insurance?
  • Can I get help with travel expenses or accommodation if I need it?

Video: What is radiotherapy?

If you have cancer, radiotherapy may play a big role in your treatment plan. Learn more in this short video.

This information was last reviewed in June 2016
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