Stereotactic radiosurgery for brain tumours

Stereotactic radiosurgery (SRS) is a way of giving radiotherapy to a brain tumour. It is given as a single high dose of radiotherapy, to a small area. Sometimes it may be divided into smaller doses given over a number of days. This is called stereotactic radiotherapy (SRT). Each daily dose is called a fraction. Stereotactic radiosurgery does not involve any surgery.

There are different ways of giving SRS. SRS can be given as 1 or more beams that move in an arc shape around the tumour. Other ways include using many small, thin radiotherapy beams given from different angles. These beams cross over at the tumour.

Giving SRS in this way means the dose is focused within the tumour, while limiting the dose to the surrounding areas.

SRS is not suitable for everyone with a brain tumour. It is usually only used to treat small tumours that are not close to important structures in the brain. Whether you can have SRS may depend on: 

• the size of the tumour
• where the tumour is in the brain
• the type of tumour
• the number of tumours in the brain.

SRS can be used to treat brain metastases. These are brain tumours which have spread from cancers in other parts of the body. SRS can be given as a main treatment, or in combination with surgery.

SRS can also be used to treat some small non-cancerous (benign) primary brain tumours such as:

• vestibular schwannoma (also called acoustic neuroma)
• meningioma
• pituitary gland tumour.

Before you have SRS, it needs to be planned. This is an important part of your treatment. Planning makes sure the radiotherapy is aimed precisely at the tumour and avoids nearby healthy areas of the brain as much as possible.

Your treatment may be planned on the same day as it is given, or at an earlier appointment. Your radiotherapy team will tell you what to expect.

When having radiotherapy to your brain, you will be asked to wear a radiotherapy mask or headframe. This helps to hold your head and neck still and in exactly the right position. This will help make your treatment as accurate and effective as possible.

Masks

Masks are usually made from plastic mesh that is moulded to fit the shape of your face. You may have a mask made on the same day that your treatment is planned, or at an earlier appointment.

For your treatment, you lie on a treatment couch. The mask is gently placed over your face and fixed to the couch. The mask should be tight but not uncomfortable. You can breathe normally while you are wearing it.

We have more information about how radiotherapy masks are made.

Head frames

For some types of SRS, you wear a lightweight plastic or metal head frame. If you are having SRT, you will not need a head frame.

The frame sits around your head and stays firmly in place by pressing against your skull at 4 points. This sounds scary and it may be a bit uncomfortable, but it should not be painful. You have local anaesthetic to numb the 4 points where the frame will push into your skin. Your team gently position the frame around your head.

Head frames are usually fitted on the same day that you have SRS.

Some types can be fitted, then taken off until your treatment session. Others are fixed. This means you wear the frame all day until your treatment session is over. You can move around with it on and can eat and drink normally. It can help to wear tops that button or zip up, because it can be difficult to take clothes off over your head.

For your treatment, the frame is fixed to the treatment couch. At the end of your treatment session your team gently removes the frame from your head. The frame will leave 4 tiny wounds on your skin. These usually heal in a few days. Your radiotherapy team will give you information about how to care for these small wounds. If the wounds feel sore, ask them about painkillers.

Support

You may feel very nervous about wearing a mask or head frame. You may want to bring some calming music or a relaxation podcast to listen to during your treatment. Most people cope well with the support of the radiotherapy team. If you are worried or uncomfortable, tell them, so they can help you.

Before you have your treatment, you have a brain CT scan (as part of radiotherapy planning) and a brain MRI scan. Your radiotherapy team uses information from the scans to plan your treatment.

The radiotherapy team helps you get into position for the scan. You lie on a treatment couch in the same position you will be in for treatment. The mask or head frame is gently fixed to the couch, so your head and neck do not move during the scan. If you are uncomfortable, tell the staff. They may be able to adjust the mask or frame slightly or help you move into a more comfortable position.

During the scan you may be alone in the room. Your radiotherapy team can see, hear and talk to you, and are close by if you need them at any time.

Your radiotherapy team will talk to you about any medications you take. It is important to tell them if you have any allergies. If you take painkillers, they may suggest you take them before your treatment so that you are comfortable.

Radiotherapy can cause some swelling of the area being treated. This can cause side effects or make any symptoms of the brain tumour worse for a time. Your doctor will give you steroids to take before your treatment to help this. They may also give you medicines to help reduce the risk of a seizure (fit). You usually keep taking them for a short time after finishing treatment. Follow your doctor’s instructions carefully and do not stop taking the steroids without your doctor’s advice.

Side effects can depend on which area of the brain has been treated and the dose of radiation given. Your doctor will explain the likely side effects of your treatment. Some side effects are mild and easy to cope with. Others may be managed with drugs or other treatments.

You may develop some of the side effects mentioned. You are unlikely to have them all. Side effects may include tiredness, headaches and feeling sick. We have more information abou side effects after radiotherapy for a brain tumour.

Side effects usually get better gradually 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 feel upset or worry that treatment is not working. But this is usually a normal reaction to the radiotherapy. It may also happen because your steroids have been reduced or stopped.

Sometimes healthy cells in the treated area can become damaged from the treatment. This is called radiation necrosis. This can happen years after having the treatment. These may include headaches, feeling drowsy or memory loss. Symptoms of this depend on the area that was treated. Your specialist doctor or nurse can tell you more about this.

Tell your radiotherapy team about any side effects. They may give you drugs to help and practical advice about managing side effects.

After treatment, you will have regular check-ups with your doctor and nurse. Sometimes SRS causes side effects that develop months or even years later. These are called late effects.

Your radiotherapy team will explain your risk of these before you agree (consent) to have SRS. You can use your follow-up appointments to talk to your doctor about any side effects, or other worries you have. They can tell you about ways to help manage the side effects.