Neurosciences - Stereotactic Radiosurgery and Stereotactic Radiotherapy

This leaflet tells you about stereotactic radiosurgery/radiotherapy (SRS/SRT) which is a highly targeted type of radiotherapy treatment. The Christie at Salford Royal is a specialised treatment centre, and patients attend for treatments that are not available in other nearby hospitals.

The unit is staffed by The Christie radiotherapists and, in addition to radiotherapy treatment for more common tumours, has facilities to treat patients with more advanced radiotherapy techniques including SRS/SRT.

The Christie staff and the Salford Royal neurosciences teams, which specialise in treating abnormalities of the brain and spine, work closely together so that patients having SRS/SRT benefit from the expertise of doctors and staff from both hospitals.

It is important that your family and friends feel well-informed and understand what is happening. Please share this information with them. Families and carers can have a role in helping you. If you would like more detailed information, please ask a member of staff who is caring for you.

The aim of this leaflet is to explain the general process and side effects of having stereotactic radiosurgery/radiotherapy.
 
If you have questions about your specific diagnosis, why this treatment is being suggested for you or alternative treatment options, you should discuss them with your doctor because everyone is different and the best treatment for each patient is decided on an individual basis.

This leaflet describes:

• What stereotactic radiosurgery/radiotherapy (SRS/SRT) is
• The planning process
• The effects that you may experience during and after treatment
• How best to cope with these effects, and where to get help and support

We treat each patient as an individual and the effects of treatment may vary from one patient to another.

Your doctor, specialist radiographer and clinical nurse specialist will explain your treatment in more detail.

What is Stereotactic Radiosurgery/Radiotherapy (SRS/SRT)?

Radiotherapy is the use of X-rays to treat tumours. It works by damaging tumour cells in a way that aims to stop them from growing.

Stereotactic radiosurgery/radiotherapy is a very precise and accurate method of giving a high dose of radiotherapy to small areas of the brain, increasing the chances of controlling your tumour, whilst at the same time minimising the amount of healthy tissue treated. This helps to reduce the chance of possible side effects from the treatment.
 
Stereotactic radiosurgery/radiotherapy may be used in selected cases either following neurosurgery, as an alternative to neurosurgery or in certain cases where patients are not suitable for neurosurgery. The aim of SRS/SRT is to control or eliminate abnormal tissue.

It can be used for a wide range of abnormalities including malignant (cancerous) tumours, benign (non-cancerous) tumours, over-growths of blood vessels (arteriovenous malformations) and other conditions.

Agreeing to treatment

For stereotactic radiosurgery/radiotherapy we will ask you to sign a consent form to say that you agree to have the treatment.

It is important that you understand the possible risks and intended benefits of any treatment that you are offered. These will be discussed with you before you sign the consent form.

You will be given a copy of the consent form and this leaflet to take home and consider before you start treatment. Consent may be withdrawn at any time before or during treatment. Should you decide to withdraw your consent, then a member of your treating team will discuss the possible consequences and alternative treatment options with you.

All treatments have some risks and it is important that you understand what these are. Of course, every attempt is made to minimise any risk to you, and we will carefully monitor you both during and after treatment. During your treatment preparation you will have opportunities to discuss anything that you do not understand.

Radiation can be harmful to the unborn child. It is important to let the radiographers know if you have missed a period, or suspect that you might be pregnant before you are exposed to any radiation.

The planning process

Planning of your stereotactic radiosurgery/radiotherapy is a complex process which involves several stages and visits to the department.

This will include visits to:

• The Mould Room where your mask is created
• The CT Simulator where a CT scan is performed to aid with the planning of your treatment
• The MRI Scanner where an MRI scan is performed to aid with the planning of your treatment
• Radiotherapy Treatment Room where you will have your treatment.

The Mould Room

To make sure your treatment position is exactly right all the way through your treatment, it is very important that we keep you very still and supported.

You will need to wear a close-fitting treatment mask. This mask is individually made to fit you and needs to be worn at each stage of your planning and treatment. The Mould Room appointment, where the mask is made, will last approximately 45 minutes.

How is the mask made?

The radiographers will construct your mask. Before beginning they will explain everything in detail. They will ask you to remove your outer clothing in the neck and upper chest area and then they will help you to lie flat on a treatment couch.

A neck rest is used to support your head. They will use warm plastic to take an impression of the back of your head.
 
A second piece of plastic is used to take an impression of the front of your head, covering your forehead, bridge of nose, upper lip and chin.

A third piece of plastic is used to take a further impression of the front of your head. This plastic sheet is full of small holes, so you will be able to breathe normally.

The radiographers will secure the plastic sheets to the head rest on the couch so you will hear some popping noises. Once it is fixed you should not be able to move your head.

Will having the mask made be uncomfortable?

The plastic is warm as it goes on and it will be allowed to cool. This is not uncomfortable, some people find it quite relaxing.

As the plastic sheet cools it ‘shrinks’ a little and you will feel it become quite tight. This is intentional and though it may feel a little uncomfortable and restricting, you should not experience any pain.

Many people, especially if they are a bit claustrophobic, worry about having a mask made however, most people cope very well.

CT Scan

After the mask is made, the next step is usually a CT scan, which we need to plan your treatment. This is an X-ray (CT) scan taken with you lying on a couch in the position necessary for your treatment.

The radiographers will explain everything in detail at the start.

• You will wear your mask during the scan to keep you in the correct position
• Scanning usually takes around fifteen minutes and during this time the radiographers will watch you on closed circuit TV.

MRI Scan

A more detailed MRI scan will need to be performed to aid in the planning of your treatment. An MRI scan uses magnetic fields to take very detailed pictures of the tumour; most people referred for SRS/SRT will have had MRI scans before.

Even if you have recently had an MRI scan, another one will generally be required to gain the relevant information. You will not need to wear your mask for this scan.

Scanning requires you to lie flat on a couch which passes through a tunnel and can be noisy. It usually takes around 30 minutes and during this time the radiographers will watch you on closed circuit TV.

For this scan, most people will need an injection of contrast (dye) to help show up the tumour more clearly. This will be done just before the radiographers start the MRI scan.

How is my treatment planned?

Before your course of radiotherapy can begin, we need to produce an individual treatment plan for you. This makes sure that all the area needing treatment is included and that healthy tissues are avoided as much as possible.

Our planning team will enter all the information from your CT and MRI scans into a planning computer and design your individual treatment plan.

The final plan will use several X-ray beams to deliver treatment to the tumour or abnormality.

When will I start my treatment?

Dependent on what area is being treated, treatment can start between a few days and a few weeks after the CT scan visit.  Sometimes we need to make small changes to your plan. If this is necessary, we may have to delay the start of treatment a little, but we will explain this to you.

How should I prepare for the treatment?

When the treatment is given, there is a risk of swelling of the area that has been treated. Any swelling is inside the brain, not usually on the skin. To prevent this, we normally recommend that you take medication called dexamethasone, starting on the morning of your treatment. This is a strong steroid that helps to prevent swelling of this kind. We can give you the medication when you come in for your planning appointment.

Whether you need dexamethasone, what dose and how long it is recommended for will vary for different people, depending on your diagnosis and treatment. Your doctor, nurse or radiographer will discuss this with you. You should continue to take all your other usual medication.

We would like a family member or friend to accompany you for your treatment. Although you are unlikely to feel different after your treatment, some people can experience some light headedness or dizziness. For this reason, we recommend that you do not drive yourself home after the treatment.

What happens when you have your treatment?

Radiographers operate the radiotherapy machines to give you the precise treatment prescribed by the doctor. They will ask you to remove any clothing or jewellery including earrings and religious headwear that are in the area being treated.

The radiographers will help you on to the treatment bed, put your mask on you and adjust the bed and the machine to the exact positions that are needed.
 
During the treatment you need to keep as still as possible. The radiotherapy machines are quite big and if you have never seen one before you might feel anxious. There is no need to worry – the treatment is painless.

Once your treatment has been set up and the radiographers are happy that everything is in the correct position, they will leave the room to take some X-ray pictures and deliver the treatment. They will be watching you carefully on a closed circuit television system.

The treatment is normally given from several different directions (beams) depending on your individual treatment plan.

It may only take a few minutes to deliver each beam but the whole treatment session may take up to 40 minutes per treatment area. Some people worry that they will be enclosed by the machine, but this will not happen.

The machine can move around you, but nothing will press down on you. The treatment machines make a buzzing noise when they are switched on. This is how you will know when the treatment is happening.

If you become worried, anxious or do not feel well while the treatment is being given, just raise your hand and the radiographers will interrupt the treatment and come to see you immediately.

The prescribed radiation dose, the number of treated areas and the number of days over which treatment is given vary between patients. Your doctor will discuss this with you.

Side effects of treatment

Side effects can be mild or more troublesome depending on the radiotherapy dose and the length of your treatment.  Radiotherapy can cause general side effects such as tiredness, but there are some effects which are specific to having radiotherapy to the brain.

While you are having radiotherapy, it is very important that you continue to take the medication prescribed by your doctor. Do not change anything unless you have discussed this with your doctor first.

Blood Glucose Measurement

We will measure your blood glucose before and during treatment. You will be prescribed a course of steroids that can sometimes affect your readings. Please inform the team if you are diabetic.

Headaches

Headaches are a very common side effect of radiotherapy to the brain. These may be due to increased swelling because of the treatment. You may be prescribed a drug called dexamethasone for this. You can also take painkillers to help you such as paracetamol.

Tiredness

Radiotherapy often makes people feel tired. It can last for several weeks after the treatment has finished. Take rests when you need to but try to maintain your normal daily activities as much as you can because we know that this can be beneficial.

Nausea (feeling sick)

Occasionally some people may have feelings of sickness. This can usually be effectively treated by anti-sickness drugs which your doctor can prescribe.

Hair loss

Occasionally some people may find that they lose small patches of hair in the area being treated. Hair loss may occur within the first 4 weeks after treatment and usually grows back.

Seizures

There is a slight increased risk of a seizure (a fit) after your treatment, although this is usually only a problem for people who have had seizures in the past. If this happens please contact the specialist radiographers or your doctor.

Scalp redness

Some patients may experience some mild redness of the scalp at the point where the radiation beams enter the brain. This is usually mild and settles without requiring treatment. If troublesome, your doctor can supply some cream to help alleviate this.

Radiation necrosis

This may occasionally occur at the treated site a few months after SRS and is due to an inflammatory reaction in the brain to high dose radiation. In most cases patients will not experience any symptoms; however, a small proportion of patients may need treatment such as steroid medication for this condition. If you have any further questions regarding this, please ask your doctor.

If you have any problems or concerns about side effects after your treatment, please contact the SRS specialist radiographers on 0161 918 7825 between 8.00am and 6.00pm or contact your GP.

After the treatment: follow-up and scans

Your side effects may last for some weeks after the treatment finishes, so it is important to take all medicines as prescribed by the doctor.

Driving

All drivers who have a brain tumour are legally required to inform the DVLA of their diagnosis. The regulations are different for different diagnoses. More information is available in the Christie information leaflet ‘DVLA driving regulations: central nervous system tumours’.

Please ask for this leaflet if you require further information.

Useful websites

Website: www.christie.nhs.uk
Website: www.northerncarealliance.nhs.uk

Useful contacts

SRS Specialist Radiographers - 0161 918 7825
The Christie at Salford - 0161 918 7800
The Christie Hotline - 0161 446 3658

Consultant’s secretary:

Dr Catherine McBain - 0161 918 7008
Dr Gillian Whitfield - 0161 918 7197
Dr Rovel Colaco - 0161 918 7197
Dr Jennifer King - 0161 918 7442
Dr Claire Barker - 0161 918 7442
Dr Karan Patel - 0161 446 6632