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  • Radiotherapy for bowel cancer

    Last reviewed January 2013


    Radiotherapy uses high-energy x-rays or electron beams to kill or damage cancer cells. Radiotherapy may be given before or after surgery for some people with rectal cancer, instead of surgery, or as palliative treatment.

    During treatment you will lie under a machine that delivers x-ray beams to the treatment area, a linear accelerator.


    Each treatment only takes
 a few minutes once it has started but setting up the machine and getting your position correct may mean that you are in the radiotherapy department for 20-30 minutes.

    Radiotherapy is usually given once a day, Monday to Friday, for about five to seven weeks. The number of radiotherapy treatments you have will depend on the site and extent of the cancer and your radiation oncologist’s recommendation.

    Side effects

    Radiotherapy can cause temporary or long-term side effects. Temporary side effects often appear during treatment,but some may last a few months after treatment. Some temporary side effects of radiotherapy include:

    • bleeding

    • diarrhoea

    • nausea

    • tiredness or fatigue

    • mild headaches
urinary or faecal incontinence
    • redness and soreness in the treatment area.

    Your treatment team will advise you about how to manage side effects. For example you will need to take care washing the treatment area and wear appropriate clothing and underwear to prevent rubbing or chafing. Ask a member of your radiotherapy treatment team what type of skin care products to use.

    Possible long-term side effects

    Long-term side effects are uncommon but can occur years after treatment has finished. They include:

    • infertility
    • hair loss
    • ski changes
    • bowel problems.

    Always consult your doctors if there is anything you are concerned about or if something changes.

    Effects on fertility

    For men radiotherapy to the pelvis may reduce sperm production or damage the sperm. This may be temporary or permanent. If you want to have children or are unsure what your plans are, you may be able to store sperm before treatment starts. Some doctors suggest that men try to avoid conceiving naturally for six months after radiotherapy treatments have finished.

    For women radiotherapy may lead to damage and shrinking of the vagina and premature menopause which can cause infertility. You may feel devastated if you are no longer able to have children and may worry about the impact of this on your relationship. Even if your family is complete you may have mixed emotions about experiencing menopause.

    Talking to your partner, a counsellor or to a specialist about your options can help. Cancer Council’s free booklet about sexuality and cancer may help. Call 13 11 20 for a copy.

    For further details on side effects and how to manage them contact Cancer Council 13 11 20.

    Information reviewed by:  Karen Barclay, Colorectal Surgeon, The Northern Hospital, Lecturer in Surgery, University of Melbourne, VIC; Carole Arbuckle, Cancer Nurse, Cancer Council VIC; Karen Bowers, Eat it to Beat it Strategy Project Officer, Cancer Council NSW; Darrell Bowyer, Consumer; Rebecca Foot-Connolly, Stomal Therapy Nurse, The Alfred Hospital, VIC; Bernadette Hadfield, Stomal Therapy Nurse, The Alfred Hospital, VIC; Melissa Heagney, Media and Communications Advisor, Cancer Prevention Unit, Cancer Council VIC; Dorothy King, Consumer; and Loreto Pinnuck, Stomal Therapist, Wound Consultant, Paediatric Continence Specialist, Monash Medical Centre, VIC.

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