Cancer Research UK logo.
SearchDonate
  • Search

Radiotherapy

Having radiotherapy for brain metastases

Radiotherapy uses high energy x-rays to destroy cancer cells. You might have radiotherapy to the brain if your lung cancer has spread there (metastases).

How you have radiotherapy to the brain

You can have this radiotherapy as:

  • whole brain radiotherapy 

Your doctor will tell you which treatment is best for your situation.

When you might have radiotherapy for brain metastases

Your doctor might suggest radiotherapy to the brain if your cancer has spread there. What type of radiotherapy you have might depend on:

  • the number of brain metastases you have

  • how well you are

If you have stereotactic radiosurgery, you usually have one treatment. This isn’t a type of brain surgery. It means having a very high dose of stereotactic radiotherapy to a small area. If you have stereotactic radiotherapy, you might have up to 5 treatments. You have one treatment (fraction) a day.

Whole brain radiotherapy is usually given over 5 to 10 treatments.

The planning CT scan

You usually have a planning CT scan in the radiotherapy department.

The scan shows the cancer and the area around it. You might have other types of scans or x-rays to help your treatment team plan your radiotherapy. The plan they create is just for you.

Photo of a CT scanner.

Your radiographers tell you what is going to happen. They help you into position on the scan couch. You might have a type of firm cushion called a vacbag to help you keep still.

The CT scanner couch is the same type of bed that you lie on for your treatment sessions. You need to lie very still. Tell your radiographers if you aren't comfortable.

Injection of dye

You might need an injection of contrast into a vein in your hand. This is a dye that helps body tissues show up more clearly on the scan.

Before you have the contrast, your radiographer asks you about any medical conditions or allergies. Some people are allergic to the contrast.

Having the scan

Once you are in position your radiographers put some markers on your skin. They move the couch up and through the scanner. They then leave the room and the scan starts.

The scan takes about 5 minutes. You won't feel anything. Your radiographers can see and hear you from the CT control area where they operate the scanner.

Making the mask

You might need to have a radiotherapy mask or mould made before you start treatment. They can also be called shells.

They keep the treatment area of your body still each time you have your radiotherapy. This is so your treatment is as accurate as possible.

You can see through most types of masks or moulds, as they usually have lots of small holes. Your radiographers might make marks on them. They use the marks to accurately line up the radiotherapy machine for each treatment. It is important that you are in exactly the same position each time.

It takes between 10 to 45 minutes to make a mask or mould.

Before making the mask

The mask is normally made directly against your skin. It's helpful to wear clothing that you can easily take off. You also need to take off any jewellery from that area.

Having a lot of facial hair can make it difficult to make a head and neck mask. The radiotherapy staff will advise you about any hair issues at your planning session.

Making the mask

A mould technician or radiographer makes the mask in the mould room of the radiotherapy department or during your CT planning scan.

The process of making a mask can vary slightly between hospitals. Most often they use a special kind of plastic heated in warm water or an oven so that it becomes soft and pliable. Your technician puts the plastic mesh on to your face so that it moulds to fit your face exactly. It feels a little like having a warm flannel put onto your face. You can still breathe easily, as the plastic has lots of holes in it.

After a few minutes the plastic mesh becomes hard. Your technician takes the mask off. It is then ready for use.

Photograph of a stereotactic radiotherapy mask for treating brain, head and neck cancers.

Head frame

You have a head frame fitted if you are going to have treatment from a GammaKnife machine.

Your treatment team attaches a frame to your skull using 4 pins. Before they attach the frame, you have injections of local anaesthetic so that you don’t feel any pain. As the frame is fitted, you might feel some pressure and tightness, but it usually feels better within a few minutes.

The treatment team removes the frame when your treatment finishes.

Having radiosurgery treatment.
Photograph showing woman having radiosurgery treatment.

The radiotherapy room

Radiotherapy machines are very big and could make you feel nervous when you see them for the first time. The machine might be fixed in one position. Or it might rotate around your body to give treatment from different directions. The machine doesn't touch you at any point.

Before your first treatment, your will explain what you will see and hear. In some departments, the treatment rooms have docks for you to plug in music players. So you can listen to your own music while you have treatment.

Photo of a linear accelerator radiotherapy machine.

Having treatment

To have treatment you lie on the treatment table. Because your position is so important, the radiographers may take a little while to get you ready. The radiographers attach your mask or head frame into the treatment table. They then leave the room before your treatment starts. This is so they are not exposed to the radiation. Your radiographers watch and listen to you on a CCTV screen in the next room. Tell them if you need to move or want the machine to stop. You need to lie very still. The machine makes whirring and beeping sounds. You can't feel the radiotherapy when you have the treatment. When the treatment is over, the radiographers help you out of the machine. They remove the mask or the frame and you can go back home or to the ward.

You won't be radioactive

This type of radiotherapy won't make you radioactive. It's safe to be around other people, including pregnant women and children.

Travelling to radiotherapy appointments

You might have to travel a long way each day for your radiotherapy. This depends on where your nearest cancer centre is. This can make you very tired, especially if you have side effects from the treatment.

You can ask your radiographers for an appointment time to suit you. They will do their best, but some departments might be very busy. Some radiotherapy departments are open from 7 am till 9 pm.

Car parking can be difficult at hospitals. Ask the radiotherapy staff if you are able to get free parking or discounted parking. They may be able to give you tips on free places to park nearby.

Hospital transport may be available if you have no other way to get to the hospital. But it might not always be at convenient times. It is usually for people who struggle to use public transport. Or who have any other illnesses or disabilities. You might need to arrange hospital transport yourself.

Some people are able to claim back a refund for healthcare travel costs. This is based on the type of appointment and whether you claim certain benefits. Ask the radiotherapy staff for more information about this and hospital transport.

Some hospitals have their own drivers and local charities might offer hospital transport. So do ask if any help is available in your area.

Side effects of radiotherapy for brain metastases

Radiotherapy to the brain can cause side effects. Let your doctor, nurse or radiographer know about any side effects that you have. Then they can find ways to help you.

They generally last a number of weeks. Some might last for a few months after the treatment has finished. Your doctor will tell you more about long term side effects.

Long term side effects

Your doctor will discuss with you any possible long term side effects from your type of radiotherapy.

Last reviewed: 14 Oct 2025

Next review due: 13 Oct 2028

Treatment for lung cancer

Your treatment depends on several factors. These include what type of lung cancer you have, how big it is and whether it has spread (the stage). It also depends on your general health.

What is metastatic lung cancer?

Metastatic lung cancer is when the cancer has spread from the lung and gone to another part of the body.

Living with lung cancer

There is support available during and after treatment to help you cope. This includes support from your clinical nurse specialist, cancer charities, community services, and family and friends.

Research and clinical trials for lung cancer

Current research is looking at ways to improve the diagnosis and treatment of lung cancer.

Lung cancer main page

Lung cancer starts in the windpipe (trachea), the main airway (bronchus) or the lung tissue. Cancer that starts in the lung is called primary lung cancer.

The Dangoor Education logo.

Dangoor Education

About Cancer generously supported by Dangoor Education since 2010. Learn more about Dangoor Education

Patient Information Forum. Trusted Information Creator.
Plain English Campaign award.

Help and Support

An icon of a hand shake.

Find a Clinical Trial

Search our clinical trials database for all cancer trials and studies recruiting in the UK.

An icon of two speech bubbles, indicating a conversation.

Cancer Chat forum

Connect with other people affected by cancer and share your experiences.

An icon of a landline phone.

Nurse helpline

Questions about cancer? Call freephone 0808 800 40 40 from 9 to 5 - Monday to Friday. Alternatively, you can email us.