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Radiotherapy

11-minute read

Key facts

Radiotherapy (also called radiation therapy) uses radiation (high-energy beams) aimed at a specific area of the body to kill cancer cells.
The radiation can come from a source outside your body or from sealed radioactive devices that are put inside your body.
The type of radiotherapy used will depend on the cancer, its location and how you respond to treatment.
Side effects caused by radiotherapy can be temporary or permanent.
Radiotherapy can be used alone or together with other cancer treatments to increase the chance of treatment success.

What is radiotherapy?

Radiotherapy, also known as radiation therapy, is an effective treatment for cancer. It uses radiation (high-energy beams) to kill or damage cancer cells to help prevent the cancer from growing or spreading.

Different forms of radiotherapy use different kinds of radiation, including:

x-rays — most often used
electron beams
gamma rays
proton beams

Radiotherapy is a localised cancer treatment. This means that it affects the part of your body being targeted, where the cancer is.

Radiotherapy may be given together with other treatments, such as surgery and chemotherapy.

What are the benefits of radiotherapy?

Radiotherapy uses radiation — rays of very powerful energy — to kill or damage cancer cells. Radiotherapy can be used to treat many cancers.

Like other cancer treatments, the benefits of radiotherapy may include:

achieving remission or cure
improving the effects of other treatments
relieving symptoms

Radiotherapy can be used before (neoadjuvant) or after other cancer treatments (adjuvant), to make them more effective. This can help reduce the risk of your cancer coming back.

Radiotherapy can also be used palliatively — to improve comfort and quality of life. In this case, it is used to relieve pain or other cancer symptoms. It does this by making the cancer smaller or stopping it from spreading.

Chemoradiation

Chemoradiation is when both chemotherapy and radiation therapy are given together. This increases the success of the treatments, because chemotherapy makes the cancer cells more sensitive to radiation therapy.

Chemoradiation is only used to treat some types of cancer. This depends on how sensitive these cells are to radiotherapy. Cancers that can be treated include:

brain cancer
bowel and anal (colorectal) cancers
head and neck cancers (such as mouth cancer and throat cancer)
lung cancer
cervical, uterine and vaginal cancers
oesophageal cancer
pancreatic cancer

Your medical team will plan your treatment to minimise damage to healthy cells near the cancer. They will carefully consider the best way to deliver your radiotherapy. You may need to have tests and scans so your oncologist can plan your radiotherapy.

What does radiotherapy involve?

Radiotherapy may be given:

from the outside — external beam
inside the body — brachytherapy

External beam radiotherapy (EBRT)

External beam radiotherapy is given from outside your body. The radiation beams are produced by a large machine.

Before you start treatment, you will go to a planning session. This will help your doctors work out how to position you for treatment. Depending on the area being treated, you may use:

boards
wedges
a special face mask

This position needs to be set before each treatment. Your medical team will make sure you are in the right position for every treatment session before starting the machine. This helps focus the radiation specifically on the cancer and not on your healthy tissue.

Internal radiation therapy

Internal radiation therapy (brachytherapy) uses small radiation sources that are placed inside your body, close to or inside the cancer. One benefit of this treatment is that it can target a specific area — even deep inside your body — with minimal effects on healthy cells.

The devices are very small and can be inserted using a thin tube (catheter). They produce ionising radiation, a type of radiation that destroys cancer cells.

In some people, the radiation source is placed for a short time before being removed. In others, the radiation source is put in your body and left permanently.

Depending on the type of brachytherapy you are having, while the devices are inserted, you may:

have a local anaesthetic to numb the area
have a general anaesthetic so that you're unconscious

Brachytherapy may be used alone or together with external beam radiotherapy.

How can I prepare myself for radiotherapy?

External beam radiotherapy does not hurt. During treatment, the machine won't touch you, but you may hear some buzzing noises.

The actual radiotherapy session usually takes only a few minutes.

Depending on your situation, you may have treatment as an outpatient, meaning that you can go home between sessions.

Sessions are often scheduled once a day from Monday to Friday, with a break over the weekend. This allows your treatment to be divided into smaller sessions of radiation. You may need treatment for several weeks.

External beam radiotherapy does not make you radioactive because the radiation does not stay in your body. The permanent radioactive devices used for brachytherapy usually release only small amounts of energy, so you are not considered radioactive. Your doctor will advise you if this is different in your case.

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How soon will I recover?

The length of your treatment and how soon you recover will depend on many factors, including:

the type and stage of your cancer
how well the cancer responds to treatment
how you cope with the treatment and its side effects

You may have tests or scans after finishing treatment to see how the cancer has responded. Radiotherapy continues to work for a while after treatment has finished, so you may not see the full benefits of radiotherapy for a few months.

If your radiotherapy is palliative, improvement in your symptoms is a good sign that the treatment is working.

What complications can happen?

Radiotherapy can treat many cancers but can also damage healthy cells close to the cancer cells being treated. This can lead to side effects or other complications.

The kind and severity of side effects can depend on:

your general health
the type and dose of radiation being given
the part of your body being treated
any other cancer treatments you may be having

Some people who have radiotherapy get very few side effects, while other people experience more side effects. Your side effects will in part depend on the part of your body that is having treatment.

Usually, side effects appear during or soon after treatment. Most side effects go away after treatment finishes. Sometimes radiation therapy can cause side effects months or years after treatment.

Common side effects that affect the digestive and urinary systems include:

loss of appetite
nausea and vomiting
diarrhoea
bladder issues such as urgency or incontinence

Other common side effects of radiotherapy can include:

hair loss (alopecia)
dry mouth and mouth sores
cough or shortness of breath
lymphoedema — swelling due to damage to your lymph nodes or lymph vessels
fatigue (tiredness)
dry, red or itchy skin — like sunburn

Many of these side effects can be treated and will improve over time.

Having radiotherapy near your reproductive organs can affect your fertility. This can be temporary or permanent. Your doctor can advise you on how to preserve your fertility.

Your medical team is very experienced in helping people who are receiving radiotherapy.

They can give you information and support to help manage any side effects or other complications.

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Are there alternatives to radiotherapy?

Alternative treatments to radiotherapy include:

Sometimes, different treatments are used at the same time. If one treatment does not work, your oncologist may recommend a different approach.

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What will happen if I decide not to have the procedure or it is delayed?

Diagnosing and starting cancer treatment as early as possible is important for improving survival rates and treatment success. It is your choice whether to delay or not have radiotherapy. Your doctor will talk to you about your options.

Resources and support

Dealing with cancer and cancer treatment can feel overwhelming, but there are many organisations that can help with information and support:

Cancer Council or call 13 11 20 for information about cancer and cancer treatment.
Cancer Australia for information about cancer and cancer treatment.
My Care Plan to help you plan your future after cancer.
Targeting Cancer by the Royal Australian and New Zealand College of Radiologists has resources for how to prepare and what to expect from your radiotherapy treatment.

To find out more about other cancer treatments, you can visit the healthdirect pages on:

cancer treatments
chemotherapy — strong medicines used to kill cancer cells
cancer immunotherapy — medicines that use your own immune system to target and kill the cancer cells

You can also call the healthdirect helpline on 1800 022 222 (known as NURSE-ON-CALL in Victoria). A registered nurse is available to speak with you 24 hours a day, 7 days a week.

Languages other than English

Cancer Council NSW provides cancer information in different languages.
Cancer Australia has cancer resources in languages other than English.

Information for Aboriginal and/or Torres Strait Islander peoples

Cancer Australia has resources for Aboriginal and/or Torres Strait Islander people.
Our Mob and Cancer offers information on cancer treatments and living with cancer.

Learn more here about the development and quality assurance of healthdirect content.

Last reviewed: October 2025

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Early Menopause – Chemotherapy and Radiation Therapy | Fact Sheet | Australasian Menopause Society Hub

Download: Early Menopause – Chemotherapy and Radiation Therapy | Fact Sheet MAIN POINTSChemotherapy and radiation therapy for cancer and other conditions can cause temporary or permanent loss of your menstrual periods and menopause.Before the age of 40, this is known as premature ovarian insufficiency (POI).Between the ages of 40 and 45, this is known as early menopause.Early menopause and POI can cause infertility and have short- and long-term health consequences such as heart disease, osteoporosis and memory problems.Some women who have chemotherapy remain fertile, so it is important to use contraception if you do not want to become pregnant or if your doctor advises you that it is not safe to become pregnant.Speak with your doctor about treatments and other options to manage any infertility and long-term health consequences.Chemotherapy and radiation therapy for cancer and other conditions can cause temporary or permanent loss of your menstrual periods, which can lead to menopause and infertility.If this occurs before the age of 40, it is known as premature ovarian insufficiency (POI) and between the ages of 40 and 45, it is known as early menopause. POI and early menopause can also happen for other reasons (see AMS fact sheet – Menopause before 40 and premature ovarian insufficiency).Chemotherapy and radiation therapy can be toxic to the ovariesChemotherapy or radiation therapy can cause early menopause because these treatments are toxic to the ovaries, especially when used at high doses to treat cancer. Whole-body radiation therapy and radiation in the pelvic area are more likely to affect your ovaries. At birth, ovaries contain one million immature eggs (primordial follicles). The number of eggs naturally decreases until, at menopause, less than 1000 eggs remain. When chemotherapy or radiation therapy damages the ovaries, women can have fewer remaining immature eggs and/or the immature eggs are unable to mature. Loss of your period after chemotherapy or radiation therapy can either be temporary or permanent. If your period returns, that does not necessarily mean that your fertility returns.Risk factors for entering early menopauseThe likelihood of entering POI or early menopause after chemotherapy or radiation therapy increases:with increasing agewhen there are fewer eggs in the ovaries before treatment startswith higher doses of chemotherapy or radiationwith radiation therapy of the whole body or pelvic areawith some types of chemotherapywhen doses of chemotherapy and radiation are given together.Symptoms and health consequences of POI and early menopauseThe signs, symptoms and health consequences of POI and early menopause after chemotherapy and radiation therapy include: missing your period or having infrequent periods – an early symptom of POI or early menopausemenopausal symptoms (either with or without your period) includinghot flushesmood changesproblems sleepingaching jointsdry vagina or poor lubrication during sexual arousal.psychological distress and increased risk of anxiety and depression because of:a diagnosis of cancer or severe medical illnesstreatment with chemotherapy/radiotherapy and the related longterm consequencesinfertility – women often feel confused, sad, old before their time and have mixed feelings about other women’s pregnancies.short and long-term health risks – infertility, osteoporosis and heart disease.Diagnosis of POI and early menopausePOI and early menopause are difficult to diagnose and the process can take many months. This can be a very stressful time and women should speak with their healthcare team for support and management options. Criteria for a diagnosis of POI or early menopause include:more than four months without a periodfollicle stimulating hormone (FSH) levels in the menopausal range on two occasions at least 4–6 weeks apart.Managing fertility issuesChemotherapy and radiation therapy might affect your fertility. Thinking about whether you will be able to have children and preserving your fertility can be overwhelming, especially when added to the stress of a diagnosis of cancer or other serious illness. Speak with your healthcare team and get the support you need. If losing fertility is a possibility, your doctor might be able to suggest options to try to preserve your ability to have children. Monthly injections with a gonadotrophin releasing hormone analogue during chemotherapy may help to preserve ovarian function. The most effective option is to have your eggs or embryos frozen before you begin treatment. Some women who have chemotherapy remain fertile, so it is important to use contraception if you do not want to become pregnant or if your doctor advises it is not safe to become pregnant. Some types of contraception are not safe for women with certain cancers or illnesses so talk to your doctor about what is best for you. For those who have developed POI or early menopause, some women choose to live a childfree life, while others adopt or foster children.Treatment of POI and early menopauseWomen with POI/early menopause should discuss with their doctor the possibility of using hormone therapy. In women more than 50 years of age, hormone therapy is called menopausal hormone therapy (MHT). In women who are aged less than 50, the same hormone therapy can be called hormone replacement therapy (HRT) because the treatment is replacing the hormones that the ovaries would be producing if you hadn’t had chemotherapy or radiation therapy.If you choose to use HRT, your doctor might advise you to continue this treatment until the typical age of menopause (51 years).HRT options include:oestrogen tablets, patches, gels and topical vaginal treatments – if you have had a hysterectomy (see AMS fact sheet – What is MHT and is it safe?)oestrogen plus progesterone – if you have not had a hysterectomycombined oral contraceptive pill as a replacement hormone – if you have no significant risk factors (such as risk of blood clotting, past blood clots or if you are a current smoker).Oestrogen therapy is not suited to everyone and is best avoided if you have breast or endometrial cancer. Your doctor can suggest non-hormonal options to help manage hot flushes and other symptoms. If contraception is required, hormonal options include the oral contraceptive pill or an intrauterine device plus oestrogen (usually as a patch or gel). If your doctor does not recommend hormones for your situation, discuss non-hormonal contraceptive options.Managing health risks associated with POI and early menopauseAdopting healthy lifestyle changes (see AMS fact sheets – Lifestyle and behaviour changes for menopausal symptoms and Weight management and healthy ageing) can reduce the risk of some of the health impacts associated with POI and early menopause. These health impacts include:osteoporosis or bone losscardiovascular/heart diseaselearning and memory disturbancesemotional issues.It is widely known that regular physical activity, a healthy diet and healthy sleep patterns can improve these problems, no matter what the cause. In addition, regular check-ups (including blood tests and bone scans) with your doctor can help you to manage your health.OsteoporosisOsteoporosis in women with POI and early menopause can be caused by:low levels of oestrogenlow levels of calcium in the dietsmokinglow levels of physical and weight-bearing activitysome types of chemotherapy and medications.In addition to lifestyle changes (quitting smoking, engaging in regular weight-bearing activities, and ensuring adequate dietary intake of calcium and vitamin D) women should have regular bone density scans every one or two years. Use of HRT can also help to maintain bone density.Cardiovascular or heart diseasePOI and early menopause can result in an earlier increase in the risk of heart disease in women.Taking HRT early and continuing treatment until the age of a natural menopause (50–55 years) can reduce the risk of heart disease. A healthy lifestyle and regular check-ups for high blood pressure, diabetes and fats in the blood will help you manage your heart health.Learning and memory problemsThere is evidence that chemotherapy can cause memory problems, but there is limited evidence that low levels of oestrogen affect memory.Taking HRT early and continuing treatment until the age of a natural menopause (51 years) might reduce the risk of learning and memory problems.Emotional issuesIn addition to a diagnosis of cancer (or severe medical illness) requiring chemotherapy/radiation therapy, women also have to cope with possible infertility and other long-term health impacts.It is only natural to feel distressed and some women might have anxiety and depression. Women often feel confused, sad, old before their time and have mixed feelings about other women’s pregnancies. Psychological counselling can ease this distress. Support from the woman’s partner, family and friends is also important.Support groupsIn addition to the support of family, friends and a healthcare team, some women find it useful to talk to other women in the same situation. Available support groups include:ACCESS Australia (Australia’s National Infertility Network) – www.access.org.auCancer Australia – www.cancer.org.auThe Daisy Network Premature Menopause Support Group – www.daisynetwork.orgNew Zealand Early Menopause support group - www.earlymenopause.org.nzWhere can you find more information?If your symptoms are bothering you or you feel you need more support, your doctor can help. Your doctor can tell you about the changes in your body and offer options to manage your symptoms. Other fact sheets about treatment options include:Menopause before 40 and premature ovarian insufficiencyWhat is Menopausal Hormone Therapy (MHT) and is it safe?9 myths and misunderstandings about Menopausal Hormone Therapy (MHT)Non-hormonal treatment options for menopausal symptomsComplementary medicine options for menopausal symptomsLifestyle and behaviour changes for menopausal symptomsWeight management and healthy ageingPOI/ Early menopause and osteoporosisThe Healthtalk Australia Early Menopause online resource contains women’s stories, information, question prompt list and links to services: https://healthtalkaustralia.org/early-menopause-experiences-and-perspectives-of-women-and-health-professionals/If you have any concerns or questions about options to manage your menopausal symptoms, visit your doctor or go to the Find an AMS Member service on the AMS website.

Read more on Australasian Menopause Society website

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Radiotherapy

Key facts

What is radiotherapy?