Common questions about radiation therapy

Many people with cancer have radiation therapy (also known as radiotherapy). Research shows that at least one in two people with cancer would benefit from radiation therapy.

Click on the common questions below to learn the answers:

How does radiation therapy work?

Radiation therapy kills or damages cancer cells in the area being treated. Cancer cells begin to die days or weeks after treatment starts, and continue to die for weeks or months after it finishes. Although the radiation can also damage healthy cells, these tend to be less sensitive than the cancer cells and can usually repair themselves. You should not feel any pain or heat during radiation therapy, but some side effects can cause pain or discomfort. Read about ways to prevent or manage side effects.

How is radiation therapy given?

There are two main ways of giving radiation therapy:

External beam radiation therapy (EBRT)

Radiation beams from a large machine are aimed at the area of the body where the cancer is located. The process is similar to having an x-ray. You will lie on a treatment table underneath the machine, which will move around your body. You won’t see or feel the radiation, although the machine can make noise as it moves. Learn more about External beam radiation therapy.

Internal radiation therapy 

A radiation source is placed inside the body or, more rarely, injected into a vein or swallowed. The most common form of internal radiation therapy is brachytherapy, where temporary or permanent radiation sources are placed inside the body next to or inside the cancer. Learn more about internal radiation therapy.

You may have one or both types of radiation therapy, depending on the type of cancer and other factors.

Where will you have treatment?

Radiation therapy is usually given in the radiation oncology department of a large hospital or treatment centre, or in private clinics. The large machines used for external beam radiation therapy will be in a dedicated room.

While treatment schedules vary, most people have radiation therapy as an outpatient. This means you do not stay in hospital, but travel to the treatment centre for each session.

Radiation therapy centres will try to arrange treatment times that suit you. For some types of internal radiation therapy, you will need to stay in hospital overnight or for a few days.

Why have radiation therapy?

Research shows that about one in two people with cancer would benefit from radiation therapy.

It can be used for different reasons:

  • As the main treatment to achieve remission or cure – Radiation therapy may be given as the main treatment with the aim of causing the signs and symptoms of cancer to reduce or disappear. This is called curative or definitive radiation therapy.
  • To help other treatments achieve remission or cure – Radiation therapy is often used before (neoadjuvant) or after (adjuvant) treatments such as surgery to make the treatment more effective. It can also be used at the same time as some treatments – when it is combined with chemotherapy, it is known as chemoradiation or chemoradiotherapy.
  • For symptom relief – Radiation therapy can help to relieve pain and other symptoms by making the cancer smaller or stopping it from spreading. This is known as palliative treatment.

Can you work during radiation therapy?

Many people can continue to work during their treatment and feel well enough to do all their usual activities. Others may need to reduce their hours or take time off. How much you will be able to work depends on the type of radiation therapy you have, how the treatment makes you feel and the type of work you do. You may be able to organise your radiation therapy appointments for the beginning or end of the day.

Talk to your employer about your working arrangements. Explain that it is hard to predict how radiation therapy will affect you, and discuss the options of flexible hours, modifying duties or taking leave.

Your treatment team will encourage you to be as active as possible, and they can answer your questions about working during treatment.

Can you have radiation therapy if you are pregnant?

You probably won’t be able to have radiation therapy if you are pregnant, as radiation can harm a developing baby. It’s important that you don’t become pregnant during the course of treatment. If you suspect you may be pregnant at any stage, it is important to tell your doctor. Men who have radiation therapy should avoid getting their partner pregnant during treatment and for about six months afterwards, as radiation can damage sperm.

Your doctor will be able to give you more information about radiation therapy and pregnancy.

How do you prepare for radiation therapy?

The effects of radiation therapy depend on the part of the body being treated and the number of treatments required. Your treatment team will tell you the likely effects for you. It can be hard to know how to prepare, but a number of general issues are worth considering in advance.

  • Explore ways to relax — Waiting for and having radiation therapy can make people feel anxious. Take something to read or listen to while you wait, ask a friend or family member to keep you company, or try chatting to other people waiting for treatment. To help you relax during the session, try meditation or breathing exercises, or ask the radiation therapists if you can listen to music.
  • Find out about quitting — If you smoke, try to quit or cut down before radiation therapy starts as smoking may make the treatment less effective and side effects worse. Quitting can be difficult, especially if you’re already feeling anxious about the cancer diagnosis, so it is important to seek support – talk to your doctor or call Quitline on 13 7848.
  • Organise help at home — You may become very tired during the later weeks of treatment. Some support with housework, meals and errands can ease the load. If you have young children, you may need to arrange for someone to look after them during treatment sessions and possibly afterwards. Older children may need lifts to and from school and activities. Consider asking one friend or family member to coordinate offers of help.
  • Arrange transport — Talk to the hospital social worker or clinic receptionist about parking arrangements as there will often be spots set aside for radiation therapy patients. At first, you may feel well enough to drive yourself or catch public transport to radiation therapy sessions. However, you are likely to feel more tired as the treatment goes on, so try to arrange for a relative, friend or volunteer to drive you. You may be able to get community transport through your local council or Cancer Council.
  • Mention metal implants — Let your treatment team know if you have any medical devices in your body, such as a pacemaker, cochlear implant or another metal implant. Radiation therapy can affect these devices.
  • Ask about travel assistance — If the treatment centre is a long distance from your home, you may be eligible for financial assistance towards the cost of accommodation or travel. Your local Cancer Council may also provide accommodation services. For details, speak to the hospital social worker or clinic receptionist, call Cancer Council 13 11 20, or go to Accommodation and transport.
  • Discuss your concerns — Keep a list of questions for your treatment team. If you are feeling anxious about the diagnosis and treatment, try talking to a member of the radiation therapy team, your GP, or a family member or friend. You can also call Cancer Council 13 11 20 to speak to a health professional.
  • Consider fertility — Some types of radiation therapy can affect your fertility. If you think you may want to have children in the future, talk to your treatment team about your options before radiation therapy begins.

How will you know the treatment has worked?

Because cancer cells continue to die for weeks or months after treatment ends, your radiation oncologist most likely won’t be able to tell you how the cancer is responding during treatment. However, they can help you manage any side effects. After treatment finishes, you will have regular checkups.

Your radiation oncologist will do a physical examination and arrange tests or scans to check whether the cancer has responded to treatment. It may be some time after radiation therapy finishes before the full benefit is known.

If radiation therapy is given as palliative treatment, the relief of symptoms will indicate that the treatment has worked. This may take a few days or weeks. Until then, you may need to have symptoms treated in others ways, e.g. medicine for pain.

This information was last reviewed in December 2017
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