Radiotherapy for a brain tumour

Radiotherapy uses high-energy rays to destroy tumour cells, while doing as little harm as possible to normal cells. Newer ways of giving radiotherapy to the brain are designed to limit the damage to healthy brain tissue.

You may have radiotherapy:

  • as your main treatment
  • after surgery, if a tumour cannot be completely removed
  • after surgery, to reduce the risk of the tumour coming back
  • with chemotherapy, if you have a high-grade glioma
  • if a tumour comes back.

There are different types of radiotherapy. They can be used in different ways to treat a brain tumour. Your treatment is carefully planned by a radiotherapy team. This includes a clinical oncologist and radiographers, who are experts in giving radiotherapy treatment. Your team will explain your treatment plan, the dates and times of your appointments and what to expect.

Standard external beam radiotherapy for a brain tumour

Radiotherapy for a brain tumour is given from a radiotherapy machine outside the body. This is called external beam radiotherapy. It is normally given as a number of short, daily treatments in a radiotherapy department. Each daily treatment is called a treatment fraction. There are different types of radiotherapy machine. The most commonly used machine is called a linear accelerator (LINAC).

The treatments are usually given 5 days a week, from Monday to Friday, with a rest at the weekend. Some people only have treatment 3 days a week. Your treatment may last from 2 to 6 weeks, depending on the type of tumour and its size.

Usually, each appointment takes about 10 to 30 minutes. But the actual treatment only takes a few minutes.

Stereotactic radiotherapy

Stereotactic radiotherapy (SRT) is a way of accurately focusing external beam radiotherapy. This means the tumour gets the treatment but there is less risk of damage to nearby areas of the brain.

SRT can be given:

  • in the same way as standard external beam radiotherapy, using short, daily treatments over several weeks
  • as a few sessions of higher dose treatment
  • as a single higher dose treatment – this is called stereotactic radiosurgery (SRS).

SRT is not suitable for everyone with a brain tumour. Your doctor can tell you if it is a suitable treatment for you and what to expect.

SRT can be given using a LINAC machine. It may also be given using a machine only used for SRT, such as Gamma Knife™ or CyberKnife™. A session of treatment can take from about 15 minutes up to 4 hours, depending on the type of machine used.

Proton beam therapy

Proton beam therapy is a type of external beam therapy that uses protons instead of high-dose x-rays. It is given using different equipment that is not available in all UK hospitals.

Proton beam therapy is recommended for some rare types of brain tumour. If you have one of these types of tumour, your doctor will explain if this treatment might be suitable . If you need this treatment you will usually have to travel to a different hospital, or even abroad.

We have more information about having proton beam therapy.

Masks and headframes

During radiotherapy you may need to wear a light-weight mask that covers your face and the front of your head. This helps you stay still in the right position and makes the treatment as accurate as possible.

Masks are usually made from plastic mesh that is moulded to fit the shape of your face.

For some types of SRT, including SRS, you wear a light-weight metal head frame. We have more information about stereotactic radiotherapy (SRT) and stereotactic radiosurgery (SRS).

You may feel very nervous about wearing a mask or head frame. Most people cope well with the support of the radiotherapy team. If you are worried or uncomfortable, tell them, so they can help you.

Planning your treatment

Before you have radiotherapy, you have a brain CT scan or MRI scan. Your radiotherapy team use information from the scan to plan how the machine will give your treatment. Usually you only need one visit but sometimes you may have a few visits to the radiotherapy department to plan your treatment.

The radiographers help you get into position for the scan. You may need to take off some clothes and wear a hospital gown. You lie on a treatment couch in the same position you will be in for treatment. If you need a mask or head frame, the radiographers gently fix this to the couch.

The radiographers may make a few ink marks on the mask or head frame. These marks will help them make sure you are in the correct position for each session of radiotherapy.

During the scan you will be alone in the room. The radiographers can see, hear and talk to you and are close by if you need them.

Having radiotherapy to the brain

When you have the treatment, you lie in the same position as you did for the planning scan. The radiographers will help you and make sure you are comfortable. They will tell you how long your treatment will take. When you are in the correct position, they leave the room and you are given your treatment.

The treatment itself is not painful. You may hear a slight buzzing noise from the radiotherapy machine. Depending on the type of radiotherapy machine, there may be equipment that moves around you during the treatment, or the couch you lie on may change position slightly.

In some treatment rooms you can listen to music to help you relax. If you would like to listen to your own music, ask your radiotherapy team if this is possible.

During the treatment the radiographers can see you at all times on a screen. They can also hear and talk to you through microphones and speakers in the treatment room.

Driving and radiotherapy to the brain

You must not drive while you are having a course of radiotherapy for a brain tumour. We have more information about brain tumours and driving, and contacting the DVLA or DLA.

Side effects of radiotherapy to the brain

You may develop side effects during or after your treatment. These can depend on which area of the brain has been treated and the amount of radiotherapy given. Your radiotherapy team will explain what is likely with your treatment. Some side effects are mild and easy to cope with. Others may be managed with drugs or other treatments.

Side effects usually improve over a few weeks or months after your treatment. Sometimes side effects or symptoms of the brain tumour get worse for a while after treatment has finished. If this happens, you may worry that the treatment is not working. But it is usually a normal reaction to the radiotherapy. Side effects may also happen if your steroids have been reduced or stopped.

Tell your radiotherapy team straight away if your side effects get worse during or after treatment. They can give you advice on how to manage them.

Tiredness (fatigue)

Radiotherapy often makes people feel tired. Tiredness may get worse as treatment goes on. If you are having radiotherapy alongside other treatments, such as surgery or chemotherapy, you may feel more tired. But there are things you can do to help, such as:

  • get plenty of rest
  • do some gentle exercise, such as short walks, for about 30 minutes a day
  • eat a healthy diet and drink plenty of fluids
  • ask others for help with everyday jobs.

After treatment finishes, you may continue to feel tired for weeks or months.

Radiotherapy to the brain can cause extreme tiredness 4 to 8 weeks after treatment. You may have very little energy, feel drowsy and spend a lot of time sleeping. It gradually gets better over a few weeks.

We have more information about coping with tiredness (fatigue).


Tell your radiotherapy team if you get headaches during radiotherapy. They can give you painkillers or steroids to help.

Hair loss

Your radiotherapy team can explain how your treatment may affect your hair. You will lose some hair in the area being treated and sometimes on the opposite side of your head, where the radiation beams exit. Your hair will usually start to grow back within 2 to 3 months of finishing treatment. Sometimes it grows back a slightly different colour or thinner than before.

We have more information about coping with hair loss.

Skin irritation

Your skin in the area that is treated may:

  • redden
  • darken
  • feel sore or itchy.

Your radiographer or specialist nurse will give you advice on taking care of your skin. If your skin becomes sore or itchy or changes colour, tell them straight away. They can give you advice and treatments if needed.

Skin reactions should get better within 4 weeks of treatment finishing.

During your treatment, you are usually advised to do the following:

  • Wash your hair or scalp gently with lukewarm or cool water. Use non-perfumed shampoo or soap.
  • Pat your hair or scalp dry gently with a soft towel. Do not rub it and avoid using a hair dryer.
  • Follow your radiotherapy team’s advice about using moisturisers.
  • Wear a scarf or hat to protect your head from the sun or cold.
  • If you shave your head, use an electric razor instead of wet shaving.

Your skin in the treated area may be more sensitive to the sun after treatment. You may find that this area burns more easily. Take extra care in the sun during treatment and for at least a year afterwards. Cover up or use suncream with a sun protection factor (SPF) of at least 30.

Feeling sick

If you feel sick, your doctor can give you anti-sickness drugs (anti-emetics) to help. If you do not feel like eating, try replacing meals with nutritious, high-calorie drinks. You doctor may be able to arrange these for you, or you can buy them from most chemists.

We have more information about coping with feeling sick (nausea) and a loss of appetite.


Your doctor or nurse can tell you if treatment is likely to affect your fertility. Radiotherapy to the pituitary gland at the base of the brain may sometimes affect fertility.

We have more information about fertility in women and men.

Support from Macmillan

Macmillan is here to support you. If you would like to talk, you can do the following:

  • Call the Macmillan Support Line on 0808 808 00 00.
  • Chat to our specialists online.
  • Visit our radiotherapy and side effects forum to talk with people who have been affected by radiotherapy, share your experience, and ask an expert your questions.

Late effects of brain radiotherapy

Radiotherapy may cause side effects that develop months or, more often, some years after treatment. These are called late effects. Newer ways of giving radiotherapy are better at protecting healthy brain tissue so late effects are becoming less common.

Your doctor will talk to you about the risk of late effects before your radiotherapy starts. Tell them if you are worried about any side effects. The benefits of having radiotherapy usually far outweigh the risk of late effects.

Possible late effects depend on the area of the brain being treated. They may include the following:

  • Changes to your memory, thinking and reasoning. This is called cognitive impairment.
  • A cataract, if you have radiotherapy close to your eye. The clear lens of the eye becomes cloudy and blurred and you cannot see as well. Cataracts can usually be easily treated with a small operation.
  • Changes in hormone levels if your treatment involves the pituitary gland or part of the brain called the hypothalamus. This can cause different symptoms, including changes to periods (menstrual cycles), changes to your sex drive or severe tiredness.
  • A second cancer in the treated area years later. This is rare.

After treatment, you will have regular check-ups with your doctor and nurse. Tell them about any side effects so they can help.

Date reviewed

Reviewed: 01 October 2019
Next review: 01 October 2021

This content is currently being reviewed. New information will be coming soon.

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