What is radiotherapy?

Radiotherapy uses radiation, such as x-rays, gamma rays, electron beams or protons, to kill or damage cancer cells and stop them from growing and multiplying. It is a localised treatment, which means it generally only affects the part of the body where the radiation is directed.

How does radiotherapy work?

Radiotherapy damages cancer cells in the region being treated. Although the radiation can also damage normal cells, they can usually repair themselves. During this repair process, you may experience some side effects, depending on the part of your body being treated.

Why have radiotherapy?

Many people diagnosed with cancer will have radiotherapy as part of their treatment. Research shows that at least one in two people recently diagnosed with cancer would benefit from radiotherapy. It can be used for several reasons:

  • Cure – Radiotherapy given with the aim of curing the cancer on its own or combined with other treatments, such as surgery or chemotherapy. This may be called curative treatment.
  • Control – Radiotherapy used to control the cancer by making it smaller or stopping it from spreading.
  • Help other treatments – Radiotherapy is used before (neoadjuvant) or after (adjuvant) other treatments. The aim is to make the main treatment more effective.
  • Symptom relief (palliative treatment) – Radiotherapy is often able to relieve symptoms, such as pain or bleeding, to help you to feel as well as possible.

How is radiotherapy given?

It can be given in two ways:

  • External radiotherapy – You will lie on a treatment table underneath a machine, which aims radiation beams towards your body. The machine remains outside of your body and doesn’t come into contact with you. Radiation beams are directed towards the cancer and surrounding tissues where the cancer may have spread.
  • Internal radiotherapy – A radiation source is put inside the body on or near the cancer. This includes brachytherapy, where a temporary or permanent radiation source is put inside the body on or near the cancer, or radioisotope treatment, where a radioactive isotope is given as a capsule.

Depending on the type and size of the cancer, and where it is in your body, you may have one or both types of radiotherapy.

Where will I have treatment?

Radiotherapy is delivered by specially trained staff called radiation therapists.

It uses large medical equipment that takes up a lot of space, so treatment is usually given in large hospitals or private clinics, in dedicated rooms.

Radiotherapy departments are run in different ways, so procedures may vary slightly. While the information in this booklet will apply in most cases, you may find things are done a little differently at the place where you’re being treated.

Travelling to treatment

While treatment schedules can vary for individuals, most people have radiotherapy on an outpatient basis. This means they do not stay in hospital, but travel to the radiotherapy department for each session.

If you are driving to the treatment centre, you may find you feel tired after a few weeks of treatment. At this stage, you may want to arrange for a family member or friend to drive you to treatment.

If you have to travel a long way each day to treatment, you may be able to get some financial assistance towards the cost of accommodation or travel. To check your eligibility or to apply, speak to the hospital social worker or radiotherapy department receptionist, or call Cancer Council 13 11 20.

How do I know the treatment has worked?

In the weeks and months following your course of treatment, you will talk with your doctor, be examined and have some tests or scans. This will show if the cancer has responded or gone away.

Cancer cells begin to die during a course of radiotherapy and this may continue for weeks or months after treatment ends. For this reason, the health professionals treating you can’t give you progress updates on how radiotherapy is going throughout the course of your treatment. However, they can adjust the dose and help you manage any side effects.

It may be some time after radiotherapy finishes before the full benefit is confirmed. Follow-up tests will be done periodically to see if the cancer has regrown or recurred.

If radiotherapy is given as palliative treatment, the relief of symptoms will tell you if the treatment has worked. This may take a few days or a few weeks.

This information was last reviewed in February 2014
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