- Radiotherapy uses radiation aimed at a specific area of the body to kill cancer cells.
- Radiotherapy can be given from a source outside the body (externally) or through a sealed device inserted inside the body (internally).
- Radiotherapy can be used alone or together with other cancer treatments to increase the chance of treatment success.
- Radiotherapy can cause side effects, which may be temporary or permanent.
- The form of radiotherapy used will depend on the type of cancer, its location, and how you — and the cancer — respond to treatment.
What is radiotherapy?
Radiotherapy, also known as radiation therapy, is a cancer treatment that uses focused radiation to kill cancer cells or damage them so they cannot grow or spread. Different forms of radiotherapy may use different kinds of radiation including x-rays, gamma rays or proton beams.
Radiotherapy is a localised cancer treatment. This means that it targets only the area affected by cancer. Your medical team will plan your treatment to minimise damage to healthy, cancer-free cells and organs around the cancer.
How does radiotherapy work?
Radiotherapy uses radiation — rays of very powerful energy — to kill cancer cells in a specific area. It is an effective treatment for many cancers, but certain cancers respond better to radiation, for example, cancers of the head and neck.
Like other cancer treatments, radiotherapy can be used in different ways:
- Curative radiotherapy is used with the aim of curing the cancer or sending it into remission (making it undetectable for a long time).
- Adjuvant or neo-adjuvant radiotherapy is used before, after or together with other cancer treatments, such as surgery and chemotherapy, to make the treatments more effective.
- Palliative radiotherapy does not aim to cure cancer but is used to decrease pain or other symptoms associated with a cancer by making the cancer smaller or stopping it from spreading.
How is radiotherapy used?
Radiotherapy may be given in a few different ways:
External beam radiotherapy is administered from outside the body using equipment that sends out radiation beams. When receiving this treatment, you will sit or lie on a special bed underneath the machine. You will need to stay very still so the radiation only affects the area around your cancer. Your medical team will make sure you are in exactly the right position each time before starting the machine. Depending on the area being treated, you may be supported with boards, wedges, beanbags, or a special face mask. Radiotherapy usually only takes a few minutes in each session and it does not hurt.
Treatment is usually given on an outpatient basis, meaning that you can go home between sessions. Sessions are often scheduled daily, Monday to Friday, with a break over weekends and over the course of several weeks or months.
Internal beam radiotherapy uses small devices such as wires, needles or pellets which have a sealed radiation source inside them. These are inserted inside your body, close to or inside the cancer, to give off radiation and kill the cancer. You may have a local anaesthetic to numb the area or receive a general anaesthetic while the devices are inserted. One benefit of this treatment is that it can be given in a specific area — even areas deep inside your body — with minimal effect on healthy cells. The radioactive devices may be left inside your body temporarily or permanently, depending on the dose of radiation being used and the type of cancer being treated.
You may need to stay in hospital for a few days when getting internal beam radiotherapy. In other cases, where low-dose devices are left in your body permanently, you may be able to go home soon after they are inserted.
Your medical team will carefully consider the best way to deliver your radiotherapy. You may need to have a number of blood tests and scans to get important information about your cancer and its exact location so your doctors can plan your radiotherapy.
What are the side effects of radiotherapy?
Radiotherapy itself does not hurt but may have other temporary or permanent side effects. This might happen if radiation damages healthy cells close to the cancer cells being treated. The kinds of side effect you may experience, and how significant they are, can vary and depend on your general health, the dose of radiotherapy given, the part of your body being treated, and any other cancer treatments you may be receiving.
Some people who receive radiotherapy feel few side effects, or even none, and can carry on with everyday activities. Others experience more significant side effects. Usually, people have side effects due to radiotherapy after a few weeks of receiving treatment. They can continue for a while — even after treatment is complete.
Common side effects include:
- dry mouth and/or mouth sores
- nausea and/or vomiting
- bowel problems, such as diarrhoea
- urinary issues such as urgency or incontinence
- lymphoedema (swelling in soft tissue)
- hair loss
Many of these are temporary and resolve over time but others, such as infertility, may be permanent. Your medical team will be very experienced in helping patients who are receiving radiotherapy and can give you information and support in managing any side effects.
How long will I need radiotherapy?
The length of your treatment will depend on many factors, including the type of cancer being treated, the stage it is at, how well it is responding to treatment and your own ability to cope with the treatment and its side effects. If you are struggling with severe side effects, your doctor may discuss taking a break to give your body a chance to recover before continuing treatment.
You may have tests or scans after finishing therapy to see how the cancer responded to treatment. However, it may take weeks or months to get the full benefit since radiotherapy continues to work for a while after treatment has ended.
What other kind of cancer treatments are available?
Many different types of cancer treatment are used in Australia today. The type of treatment your doctor recommends will depend on the type of cancer, the stage, your treatment goals and your general health.
Types of cancer treatment available include:
- surgery — an operation to physically cut out a cancer
- chemotherapy — strong medicines used to kill cancer cells
- immunotherapy — medicines that use your own immune system to target and kill cancer cells
- hormone therapy — medicines that block the effects of certain types of the body’s hormones on cancer growth and spread
- targeted therapy — medicines that target specific traits of cancer cells to affect their growth and spread
- ablation (including cryo- and radiofrequency ablation) — using chemicals, extreme temperatures or radiowaves to kill areas of cancer cells
- alternative therapies — using therapies outside of mainstream medical practice
- clinical trials — taking part in trials of new medicines designed to treat cancer
Radiotherapy may be given together with other treatments, such as surgery and/or chemotherapy. Chemotherapy and radiation (also known as chemoradiation or chemoradiotherapy) given close together can make both treatments more effective.
Resources and support
Dealing with cancer and cancer treatment can feel overwhelming. There are many organisations that can help with information and support, including:
- Cancer Council for information about cancer and cancer treatment
- Cancer Australia for information about cancer and cancer treatment
- Canteen, a support network for 12-25 year-olds, and their families and carers
- McGrath Foundation for people with breast cancer and their families
- Peter MacCallum Cancer Centre for cancer information and support services
- My Care Plan, to prepare a personalised plan for after cancer
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Last reviewed: April 2021