External beam radiation therapy

External beam radiation therapy (EBRT) uses a radiation machine to precisely direct radiation beams at the cancer. The radiation is targeted only at the part of the body where the cancer is; for example, if you have breast cancer, the radiation will treat only the breast.

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The radiation therapy machine

You will lie on a treatment table or “couch” under the machine, which will usually be a linear accelerator (see illustration below). The machine does not touch you, but it may rotate around you to deliver radiation beams to the area of the cancer from different directions. This allows the radiation to be more precisely targeted at the cancer and limits the radiation to surrounding normal tissues. You won’t be able to see or feel the radiation. Once the machine is switched off, it no longer gives off radiation.

Linear accelerator

Linear accelerator

This is a general illustration of a linear accelerator (linac), the most common type of radiation therapy machine. The machine used for your treatment may look different.

How long is a course of treatment?

Your radiation oncologist will work out the total dose needed to treat the cancer. In most cases, this will then be divided into several smaller doses called fractions that are given on different days. Each session lasts about half an hour, with the treatment itself taking only a few minutes.

A course of treatment refers to the total number of sessions of radiation therapy you receive. The length of the course varies between people depending on the type of cancer, the total dose required, the location of the cancer and the reason for having the treatment.

In general, higher total doses are used for curative treatment, and a fraction will be given each day, Monday to Friday, for 3–8 weeks. Dividing the dose into separate sessions with weekend rest breaks allows the healthy cells to recover. Occasionally, the radiation oncologist may recommend two treatments per day, with several hours between the sessions.

If you are having radiation therapy as palliative treatment to relieve symptoms, you may have only one or a few treatments.

Each fraction of radiation causes a little more damage to cancer cells, so it’s important to attend all of your scheduled sessions. This ensures you receive the required amount of treatment to eventually kill the cells or relieve symptoms. When you miss sessions, cancer cells have more time to repair the damage, so your treatment may become less effective.

Click on the icon below to download a PDF booklet of Understanding Radiation Therapy.

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Instructions for downloading and reading EPUB files

Apple devices

The iBooks application must be installed on your Apple device before you can read the EPUB.
Different ways to download an EPUB file to your Apple device:

  • email EPUB files to yourself and transfer the attachment to iBooks.
  • copy EPUB files into DropBox (or a similar service) and use the DropBox app to send them to iBooks.
  • open EPUB files directly from Mobile Safari and open them in iBooks, where they are saved automatically by downloading the EPUB from the website.

Need more help? Visit: http://support.apple.com/kb/HT4059


To download an EPUB file to your Kobo from a Windows computer:

  • download and save the EPUB directly onto your desktop.
  • connect your Kobo to your computer using the USB cable and tap “Connect” on your eReader.
  • select “Open folder to view files” to view the contents of your Kobo.
  • navigate to where you have stored your EPUB file in “Finder”, in documents or downloads, and drag and drop it into the Kobo window. You can now disconnect your Kobo to read the eBook.

To download an EPUB to your Kobo from a Mac:

  • download and save the EPUB directly onto your desktop.
  • connect your Kobo to your computer using the USB cable and tap “Connect” on your eReader.
  • open your “Finder” application.
  • select “Kobo eReader” from the listed devices to view the contents of your Kobo.
  • navigate to where you have stored your EPUB file in “Finder”, probably in documents or downloads, and drag and drop it into the Kobo window. You can now disconnect your Kobo to read the eBook.

Turn on your Kobo and your EPUB will be located in “eBooks”, while a PDF will be located in “Documents”.
Need more information? Visit: http://www.kobo.com/help/koboaura/response/?id=3784&type=3

Sony Reader

To download an EPUB file on your Sony Reader™:

  • ensure you have already installed the Reader™ Library for PC/Mac software
  • select the eBook you want from our website and click the link to download it.
  • connect the Reader™ to your computer.
  • open the Reader™ Library software and click “Library” in the left-hand pane and select the eBook to view it.

Need more help? Visit: https://au.readerstore.sony.com/apps_and_devices/

Amazon Kindle 2nd Generation devices

EPUB files can’t be read on the Amazon Kindle™. However, like most eReaders, Kindle™ 2nd Generation devices are able to display PDFs. We recommend that you download the PDF version of this booklet if you would like to read it on a Kindle™.
To transfer a PDF to your Kindle™ via USB cable from your computer or Mac:

  • download the PDF directly onto your computer.
  • connect the USB cable to your computer’s USB port, and the micro USB end of the cable to your Kindle™. Note: the Kindle™ won’t be available as a reading device while it is connected to your computer until it has been disconnected.
  • open the Kindle™ drive and several folders will appear inside. The “Documents” folder is where you will need to copy or drag the PDF to.
  • safely eject your Kindle™ from your computer and unplug the USB cable. Your content will appear on the Home Screen.

Kindle also provides a Kindle Personal Documents Service that allows users to send documents as an attachment directly to your eReader. For more information on this service, visit http://www.amazon.com/gp/help/customer/display.html/ref=help_search_1-1?ie=UTF8&nodeId=200767340&qid=1395967989&sr=1-1
For more information on accessing a PDF on your Kindle™, visit www.amazon.com/manageyourkindle, log in to your account and click on Personal Document Settings.
Need more help? Visit https://www.amazon.com/gp/help/customer/display.html?nodeId=200375630

Android and PC

You can also download and open eBooks on Android devices and PCs with appropriate apps or software installed. Suitable eReader apps for Android include Google Play Books, FBReader and Moon+ Reader. Suitable software for PCs include Calibre and Adobe Digital Editions.

This information was last reviewed in December 2017
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