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Patient information - Anal cancer - External Beam Radiation Therapy

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What is radiation therapy (radiotherapy)?

Radiation therapy is the use of high energy x-rays, or other types of radiation, to treat cancer. 

External beam radiation therapy (or EBRT) is the most common type of radiation therapy delivered from outside of your body. A large machine called a linear accelerator (or linac) is used to deliver external beam radiation therapy. 

What happens during radiation therapy?

When you are having radiation therapy, you will be on your own in the treatment room. Your radiation therapists can see and hear you at all times, via cameras and microphones in the treatment room. 

During external beam radiation therapy, the machine may move around you and make buzzing sounds, but it will not touch you. 

You cannot see, feel, smell, or taste radiation.

If you become concerned or feel unwell in any way during treatment, raise your hand or call out. The radiation therapists can interrupt the treatment to attend to you.

What is the aim of treatment?

Radiation therapy is given to destroy cancer cells, shrink the tumour, ease symptoms caused by the tumour and/or improve your quality of life.

When is treatment delivered and how long does each treatment take? 

Radiation treatment is usually given every weekday (Monday to Friday) in the radiation oncology department. You will usually be an outpatient (not admitted to hospital) for treatment.

Each treatment takes about 20 minutes in the treatment room. This time includes getting you in your treatment position and delivering the radiation therapy.

Your treatment team will let you know how much time to allow for each treatment visit. A treatment visit includes time to have your radiation therapy and may need to include time to:

  • see a doctor, nurse or other health professional
  • take medications before or after treatment
  • do other tasks to prepare for treatment, such as fill or empty your bladder. 

Treatments may be delayed due to unexpected events such as equipment issues or emergency treatments. In these cases, your treatment staff will let you know what is happening.

How long is a treatment course?

A course of radiation therapy will take approximately 6 weeks to complete.

As part of your treatment, you may have both radiation therapy and chemotherapy.

You and your team of doctors and health care professionals (known as a multidisciplinary team, or MDT) will consider things such as: 

  • the type of treatments available
  • the number of treatments needed 
  • your circumstances and preferences. 

This helps to develop a treatment plan that is right for you, your family and carers.

IMMEDIATELY go to your nearest hospital emergency department, or contact your doctor or nurse if you have:
  • a temperature of 38ºC or higher.
  • chills, sweats, shivers or shakes.
  • difficulty, severe discomfort or are unable to pass urine.
  • uncontrolled nausea and vomiting.
  • uncontrolled diarrhoea.
Emergency contact details
Ask your doctor or nurse from your treating team who to contact if you have a problem.

Daytime contact:

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After hours (night/weekend) contact:

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Other instructions:

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Important information

Do not try to get pregnant or father a child during your radiation therapy treatment.

  • Radiation therapy can cause harm to eggs or sperm, and an unborn baby.
  • Use a reliable method of contraception when you have sex.
  • Ask your doctor or nurse what contraception to use during cancer treatment and how long to continue using it after treatment. 

Before starting radiation therapy, and when you are having treatment, tell your doctor, nurse or radiation therapist immediately if you:

  • Are pregnant, become pregnant, or think you may be pregnant.
  • Father a child.
How does treatment affect fertility?

Some cancer treatments can reduce your fertility. This can make it difficult or impossible to get pregnant or father a child.

Before starting radiation therapy treatment, talk to your doctor, nurse or radiation therapist about:

  • How your treatment may affect your fertility.
  • Whether you want to have children in the future.
  • Fertility sparing options that may be available to you and/or your partner.

Your doctor may refer you to a fertility specialist.

Tell your doctor or nurse if you:
  • notice any blood in your bowel motions.
  • have changes in your bladder and bowel habits.
  • develop any changes to your skin.
  • feel unwell in any way.
At home it is important to:
  • take your medications as prescribed by your doctor.

Cancer treatments can cause damage to normal cells in your body, which can cause side effects. Everyone gets different side effects, and some people will have more problems than others.

The table below shows some of the side effects you may get with this treatment. You are unlikely to get all of those listed and you may also get some side effects that have not been listed.

Tell your doctor or nurse about any side effects that worry you. Follow the instructions below and those given to you by your doctor or nurse.

Short term side effects: May occur during treatment or within a few weeks of finishing radiation therapy and usually settle within 4 weeks

Bowel irritation

  • During the last few weeks of treatment, you may have:
    • bowel motions (stools, poo) that are more urgent or frequent
    • a small amount of bleeding or clear discharge when passing a motion
    • a sore or irritated rectum
    • bloating, cramping or pain.
  • Take anti-diarrhoea medication as directed by your doctor.
  • Drink plenty of fluids (unless you are fluid restricted).
  • Avoid spicy foods, dairy products, high fibre foods, and coffee.
  • Ask your doctor or nurse for eviQ patient information - Diarrhoea during cancer treatment. 
  • Contact your doctor or nurse as soon as possible if your diarrhoea continues despite taking medication, or if you feel dizzy, light-headed or unwell.

Tiredness and lack of energy (fatigue)

  • You may feel very tired, have no energy, sleep a lot, and not be able to do normal activities or things you enjoy.
  • Do not drive or operate machinery if you are feeling tired.
  • Nap for short periods (only 1 hour at a time).
  • Prioritise your tasks to ensure the best use of your energy.
  • Eat a well balanced diet and drink plenty of fluids (unless you are fluid restricted).
  • Try some gentle exercise daily. Rest when you feel you need to.
  • Allow your friends and family to help.
  • Tell your doctor or nurse if you have problems managing any of the symptoms listed above.
  • Ask your doctor or nurse for eviQ patient information - Feeling tired (fatigue) during cancer treatment.

Skin changes

  • The skin on your pelvis may become
    • red
    • warm
    • dry
    • itchy
    • more sensitive.
  • Skin changes usually start to develop 2 to 3 weeks after the start of treatment. They usually begin to settle down about 2 to 4 weeks after treatment has finished.
  • It is important to care for your skin during treatment and for 4 weeks after treatment as directed by your treating team.
  • Do not scratch the affected area and avoid tight fitting clothing that rubs the skin.
  • Towards the end of treatment the skin around your rectum may become moist and breakdown.
  • Sitting in a salt water bath can help to clean and soothe the skin.
  • Ask your doctor or nurse for eviQ patient information - Skin changes and skin care during radiation therapy. 
  • Tell your doctor or nurse if you get any skin changes, they can help you to manage them.

Bladder problems

  • You may have
    • discomfort and burning when you urinate
    • blood in your urine.
  • You may also notice that you urinate more often, particularly at night and sometimes with a slower stream.
  • Some people may not be able to empty their bladder(retention) and this may require catheterisation (a tube inserted through the penis going to the bladder) which is usually temporary.
  • Some people have less control over their bladder (incontinence) which may be temporary or ongoing.
  • Increasing your fluid intake (unless fluid restricted) and taking a urinary alkaliniser (as advised by your doctor) may provide some relief from the burning sensation when passing urine.
  • Contact your doctor or nurse immediately, or go to the nearest hospital Emergency Department if you are unable or having difficulty to pass urine, or severe discomfort.

Hair loss

  • In the area of treatment your hair may fall out.
  • This can happen 2 to 3 weeks after starting treatment.
  • This is usually temporary, but for some people it can be permanent. 

Nausea and vomiting

  • You may feel sick (nausea) or be sick (vomit).
  • You are more likely to get these symptoms if you are having treatment to your abdomen/stomach area.
  • If you have been prescribed anti-sickness medication take it as directed, even if you don’t feel sick.
  • Drink plenty of fluids (unless you are fluid restricted).
  • Eat small meals more frequently.
  • Try food that does not require much preparation.
  • Try bland foods like dry biscuits or toast.
  • Gentle exercise can help with nausea.
  • Ask your doctor or nurse for eviQ patient information - Nausea and vomiting during cancer treatment.
  • Contact your doctor or nurse as soon as possible if you continue to vomit despite taking anti-sickness medication, or if you feel dizzy, light-headed or unwell.

Radiation induced myelosuppression

Radiation may cause a decrease in bone marrow activity meaning your body will produce fewer blood cells.

Long term side effects: May develop months to years after radiation therapy has finished and may be permanent

Bowel changes

  • For some people, their bowel habits do not return completely back to normal after treatment has finished.
  • You may get:
    • an urgent need to open your bowels
    • pain when opening your bowels
    • a small amount of bleeding or clear discharge when passing a motion
    • diarrhoea
    • constipation
    • leakage or less control over your bowel motions (incontinence).
  • Rarely, a small hole may occur in the bowel which your doctor will help you to manage.
  • Tell your doctor or nurse if you get any of the symptoms listed above, they can help you to manage them.
  • Contact your doctor or nurse as soon as possible if you have any bleeding from your rectum.

Vaginal and sexual function changes

  • Treatment to the female pelvis may cause vaginal changes including dryness and narrowing or shortening of the vagina (called vaginal stenosis).
  • These changes may be temporary or ongoing.
  • It is important to keep the vagina lining as supple as possible to reduce this.
  • You can manage vaginal narrowing by having regular intercourse or using a vaginal dilator.
  • Ask your doctor or nurse for eviQ patient information - Vaginal changes after radiation therapy to the pelvis.
  • Tell your doctor or nurse if you get any of these symptoms, they can help you to manage symptoms or refer you to someone who can help.

Sexual function

  • Men may experience changes to sexual function such as impotence or dry/painful ejaculations.
  • These changes may be temporary or ongoing.
  • Tell your doctor or nurse if you get any of these symptoms, they can help you to manage them or refer you to someone who can help.

Infertility

Early menopause

  • You may get:
    • hot flushes and night sweats
    • mood changes
    • vaginal dryness
    • irregular or no periods.
  • You may also:
    • have trouble sleeping
    • find sex painful or lose interest in sex.
  • Talk to your doctor or nurse about ways to manage these symptoms.

Swelling (lymphoedema)

  • You may get swelling in your legs.
  • Your legs may feel heavy or tight and you may have aches and pains.
  • This is caused by a build up of fluid in body tissues.
  • Tell your doctor or nurse if you notice any swelling in your limbs, they can help you to manage it.
  • Early treatment can reduce the risk and severity of swelling.
  • Ask your doctor or nurse for eviQ patient information - Lymphoedema and radiation therapy.

Pelvic fracture

  • You may be at risk of breaking a bone in your pelvis.
  • The risk can depend on the type of treatment you have.
  • Tell your doctor or nurse if you have ongoing sharp pains or soreness in your joints.

Bowel blockage (obstruction)

  • This treatment can affect the movement of faeces through the bowel, causing a blockage.
  • You may get:
    • abdominal pain
    • loss of appetite
    • nausea or vomiting        
    • constipation
    • watery diarrhoea.
  • Tell your doctor or nurse if you have any of the symptoms listed above.
  • Contact your doctor or nurse immediately, or go to the nearest hospital emergency department if you have uncontrolled pain, vomiting or diarrhoea.

Bladder changes

  • Radiation therapy can cause changes to the lining of your bladder which can be temporary or ongoing.
  • You may have:
    • discomfort and burning when you urinate
    • urgency or pass urine more often
    • blood in your urine
    • leakage or less control over your bladder (incontinence).
  • Tell your doctor or nurse if you get any of the symptoms listed above, they can help you to manage them.
  • Contact your doctor or nurse immediately, or go to the nearest hospital Emergency Department if you are unable or having difficulty to pass urine, or severe discomfort.

Developing a second cancer

  • There is a very small risk that you may develop a second cancer as a result of having radiation therapy.
  • This is uncommon and may not happen until at least 10 years after treatment.
  • Talk to your doctor if you have any concerns about the benefits and risks of radiation therapy.
Will I be radioactive?
  • You will NOT be radioactive during or after external beam radiation therapy treatment.
  • You can safely mix with other people, including children and pregnant women, at any time during and after your treatment.
Hair loss
  • You will not lose hair on your head.
  • You may lose some hair on your body if it is in the area of your radiation treatment.
  • The hair usually starts to fall out 2-3 weeks after starting your treatment.
  • In most patients this is temporary, but for some this may be permanent.
Sex and sexuality
  • The desire to have sex may decrease as a result of radiation treatment or side effects. 
  • Your emotions and the way you feel about yourself may also be affected by your treatments. 
  • It may help to discuss your concerns with your partner and doctor or nurse.
  • A referral to a sexual counsellor may help.
Pain or discomfort during sex
  • Some women find that treatment causes pain and discomfort to the tissues in their vagina. This may cause too much discomfort to have sex until the tissues have healed. This may take 4-6 weeks after radiation therapy has finished.
  • If you experience pain or discomfort during vaginal sex, it may help to discuss this with your partner, radiation oncologist and/or nurse. A referral to a sexual counsellor or pelvic physiotherapist may help you manage this side effect. 
  • The regular use of a vaginal dilator may help to keep the tissues in your vagina flexible and elastic. For more information, read the patient information sheet vaginal changes after radiation therapy to the pelvis.
Diet
  • While you are on treatment, it is recommended that you maintain a healthy diet and drink plenty of fluids.
  • Ask to see a dietitian if you have any concerns or questions about your diet, are having difficulty eating or are experiencing unplanned weight loss. The dietitian can offer advice on what to eat and drink and help you with meal planning.
Driving
  • In general, most people will be well enough to drive after each radiation therapy treatment.
  • If you are unwell or on strong pain medications discuss this with your doctor prior to driving a motor vehicle.
Vaccinations
  • Vaccines can be inactivated or live.
  • Inactivated vaccines such as flu and tetanus vaccines are safe to receive while having treatment.
  • Check with your doctor before having any live vaccines during your treatment, or for 6 months after your treatment has finished.
  • If you are unsure, check with your doctor before having any vaccinations.
Medications
  • Before you start treatment, tell your doctor about any medications you are taking, including vitamins, alternative, natural or herbal supplements.
  • Do not stop or start any medications during treatment without talking to your doctor and pharmacist first.
X-rays and other images taken during treatment
  • The x-­rays or other images that the radiation therapists take during your treatments are used to confirm that you are in the correct position for your treatment.
  • These cannot be used to tell if your tumour is responding to the radiation therapy treatment.
Treatment follow-up
  • Once your treatment has finished, your doctor will let you know what follow-up tests and appointments are needed.
How do I know if the treatment is successful?
  • It may not be possible to know if your treatment has been successful immediately after treatment.
  • Your doctor will see you after treatment is complete to discuss your progress and next steps.
Quitting smoking
  • It is never too late to quit smoking.
  • Quitting smoking is one of the best things you can do to help your treatment work better.
  • There are many effective tools to improve your chances of quitting.
  • Talk to your treating team for more information and referral to a smoking cessation support service.
Staying active
  • Research shows that exercise, no matter how small, has many benefits for people during and after cancer treatment.
  • Talk to your doctor before starting an exercise program.
  • Your doctor can advise whether you need a modified exercise program.
Who can I talk to if I am not feeling like my usual self?
  • It is common to feel overwhelmed, worried, anxious or depressed before, during and after treatment.
  • Let your treatment team know if you would like support with everyday activities or relationships, or would like someone to discuss your concerns with.
  • There are many members of your health care team and many different types of help available.
  • You can call Cancer Council on 13 11 20 for free and confidential information and support.
For more information about cancer treatment, side effects and side effect management, see our patient and carers section.

Telephone support

  • Call Cancer Council on 13 11 20 for cancer information and support

Bowel cancer information

General cancer information and support

Quit smoking information and support

Quitting smoking is helpful even after you have been diagnosed with cancer. The following resources provide useful information and support to help you quit smoking. Talk to your treating team about any other questions you may have.

This document is a guide only and cannot cover every possible situation. The health professionals caring for you should always consider your individual situation when making decisions about your care. Contact your cancer clinic staff or doctor if you have any questions or concerns about your treatment, or you are having problems coping with side effects. While eviQ endeavours to link to reliable sources that provide accurate information, eviQ and the Cancer Institute NSW do not endorse or accept responsibility for the accuracy, currency, reliability or correctness of the content of linked external information sources. Use of this document is subject to eviQ’s disclaimer available at www.eviQ.org.au

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https://www.eviq.org.au/pi/1860

06 Oct 2024