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External radiotherapy treatment

Radiotherapy uses high energy x-rays to treat cancer cells.

You have external radiotherapy treatment in the hospital radiotherapy department as an outpatient. You go to the hospital for treatment once a day, from Monday to Friday, with a break at the weekends. The length of your course of treatment varies, depending on the type and size of your cancer and on the aim of the treatment. 

Many women have a course of external radiotherapy first and then internal radiotherapy treatment after that. A daily external treatment takes around 25 minutes.

The radiotherapy room

Radiotherapy machines are very big. They rotate around you to give you your treatment. The machine doesn't touch you at any point.

Before you start your course of treatment your therapy radiographers explain what you will see and hear. In some departments the treatment rooms have docks for you to plug in your music player. So you can listen to your own music.

Photo of a linear accelerator

During the treatment

You need to lie very still on your back. Your radiographers might take images (x-rays or scans) before your treatment to make sure that you're in the right position. The machine makes whirring and beeping sounds. You won’t feel anything when you have the treatment.

Your radiographers can see and hear you on a CCTV screen in the next room. They can talk to you over an intercom and might ask you to hold your breath or take shallow breaths at times. You can also talk to them through the intercom or raise your hand if you need to stop or if you're uncomfortable.

You won't be radioactive

This type of radiotherapy won't make you radioactive. It's safe to be around other people, including pregnant women and children.

Travelling to radiotherapy appointments

Tell the radiotherapy department if you prefer treatment at a particular time of day. They can try to arrange this.

Car parking can be difficult at hospitals. It’s worth asking the radiotherapy unit staff:

  • if they can give you a hospital parking permit
  • about discounted parking rates
  • where you can get help with travel fares
  • for tips on free places to park nearby

If you have no other way to get to the hospital, the radiotherapy staff might be able to arrange hospital transport for you. But it might not always be at convenient times. To see if you're eligible they usually work it out based on your earnings or income.

Some hospitals have their own drivers or can arrange ambulances. Some charities offer hospital transport.

Last reviewed: 
17 May 2018
  • External Beam Therapy
    P Hoskin
    Oxford University Press, 2012

  • Principles and practice of oncology (10th edition)
    VT. De Vita, S. Hellman, and SA.Rosenberg
    Lippincott, Williams and Wilkins, 2015

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