RADIOTHERAPY

What is Radiotherapy:
Radiotherapy uses high energy waves (X-rays) to treat cancer. Doctors quite often use radiotherapy to treat brain tumours. It may be your main treatment if you have a brain tumour that your surgeon cannot remove. You may have radiotherapy after surgery either

• To treat any tumour that your surgeon couldn't remove
• To try to lower the risk of the brain tumour coming back in the future

Where and when you have Treatment:

You have radiotherapy treatment in the hospital radiotherapy department. You usually have the treatment as an out patient, so you have to travel to the hospital every day throughout your course of radiotherapy.
You are most likely to have radiotherapy for a brain tumour as a series of daily treatments, over as many as 6 – 7 weeks. You have one treatment a day, from Monday to Friday. If you are having a shorter course of palliative radiotherapy to help with symptoms or slow down your tumour, you will have treatment for about 2 weeks.

Planning your Treatment:

Specialists plan radiotherapy very carefully. At your first visit, you will lie under a large X-ray machine called a simulator. The doctor uses this to work out where to give your treatment to kill the most cancer cells and miss as much healthy body tissue as possible. The photo above shows the view into a simulator room from the radiographers control desk.

These days, it is usual to use 3D computerised planning. The doctors take many different scans of your brain from different angles. They then use a computer to work out

• The exact shape of the tumour
• Where important structures are in relation to the tumour (e.g. your eyes)
• The direction to aim the radiation beams so that they avoid all the important structures

Once your doctor has all the scans, it can take up to 8 hours to use them to plan your treatment. The radiotherapy beams will be exactly placed so that the radiation hits the tumour. Most healthy brain tissue will be outside the irradiated area. It may be possible for your doctor to tell you where you are most likely to lose hair before you start treatment. Generally, you lose hair from the point where the beams enter your head and also where they leave (the exit beam).

There are 2 main ways to have radiotherapy to the brain. You will either have to have a mask made. Or have a head frame fitted.

The treatment mask:
The plastic mask is sometimes called a 'shell' or 'mould'. It covers the whole of your face and the front of your head. The mask keeps your head completely still while you are being treated. You can see through it. It is made of clear plastic with eye, nose and mouth holes cut out. Any marks that the radiographers need to line up the machine can be made on the mask instead of on your skin.
You will have to go to the hospital mould room to have your mask made before you start your treatment. First of all, cool gel is smoothed all over your face. Then the mould technician covers your face with strips of plaster of paris bandage. Holes are left around your mouth and nose so that you can breathe easily. The plaster of paris sets very quickly. As soon as it is set, it is lifted off. This plaster mould is used to make a plastic mask that exactly fits your face.

Some radiotherapy departments use a type of plastic called thermoplastic to make the masks. This is soft when warm and hardens as it cools. The warmed plastic is shaped to your face and head. It does not cover your nose or mouth, so you can breathe easily. When the plastic cools, it gives an exact impression of your face and head.

You will have to visit the mould room once more. This is to make the plastic legs that attach the mask to the radiotherapy treatment table. During this visit, you may also have your radiotherapy planning. As in the picture above, you may have marks made on your mask during the planning session. These are to help the radiographers line up the radiotherapy machine very precisely when you have your treatment.

You will only have to wear the mask when you go for treatment. Once you are lying down, the mask will be put over your head and fixed to the radiotherapy treatment table on either side

This stops you from moving while you are having treatmentent
















TREATMENT PLANNING

TREATMENT MASK