What is radiotherapy?
Radiotherapy is the treatment of cancer (malignant disease) using exact, carefully measured doses of radiation. Usually, several beams of radiation are carefully and accurately directed to a specific area of the body. Each beam is called a radiotherapy “field”.
The point at which all the beams (fields) meet is where the highest dose of radiotherapy is given. You will hear the radiographers and doctors talk about fields.
Radiotherapy is painless and is similar to having an x-ray picture taken. A similar radiation is used, but in radiotherapy it is more penetrating.
Radiotherapy may be used for:
Radiotherapy works because tumour cells are more sensitive than normal cells, and so are damaged by the radiation. The normal healthy cells are also damaged, and this is what causes side effects , but they are able to repair and heal themselves.
External beam radiotherapy DOES NOT make you radioactive and it is quite safe to be with other people including children, during your course of treatment.
What is Radiotherapy Treatment Planning?
Treatment planning identifies the exact area to be treated and the most effective dose of radiation you should receive. The radiation is restricted to the tumour so healthy tissue is exposed to as little radiatin as possible. Planning sessions may last up to an hour and you will need to lie still.
Planning takes place in either a Simulator or CT Sim Scanner. A simulator is an x-ray imaging machine which can imitate the radiotherapy treatment machine. You will lie on a couch in the chosen treatment position. The simulator is moved around you to take pictures, but it does NOT touch you.
Lights are dimmed so that laser lights and field lights (indicating the area to be treated) can be seen. Exact, careful measurements are taken and recorded. This record means the treatment radiographers can chek you are lying in the correct position each time you have treatment, and that the radiation is directed to the same exact area each day.
Once the treatment area for radiotherapy has been finalised, temporary ink marks will be drawn on to your skin. You will be asked not to wash these marks off whilst you are having treatment. They may fade, but the radiographers will re-mark them when necessary. Do not try to redraw them yourself.
Permanent dots (tattoos) will also be made on your skin, with your permission, by putting a pin prick of ink under the skin. Then, if the pen marks are washed off your skin, the treatment radiographers will have an exact reference mark to set up to, to deliver your treatment.
Some patients will need to have a plastic mould made to fit the part of the body being treated. The moulds are made to ensure that you are in the correct position for treatment, and allow pen marks to be made on the mould rather than on your body. You will only wear the mould for a short time during your treatment.
They are made of clear, lightweight plastic and fit closely, but comfortably over the area being treated.
Your First Day of Treatment
It is quite normal to feel anxious on your first day of treatment. If you are worried about the radiotherapy, please tell the staff, they are there to help you. Once treatment starts, you will be more relaxed.
Once in the treatment room, you will see the LINAC machine (linear accelerator). You will need to lie on the couch as before when you had planning. The radiographers use laser lights to align you on the couch, then darken the room to see another light which indicates the area to be treated.
When the radiographers are satisfied that everything is correct and they have completed their checks they will leave the room, and you will hear a buzzing noise as they leave. This is only an interlock alarm which informs the machine that it is safe to switch on. You are in the room on your own whilst treatment is on, but the radiographers are watching you all the time on a closed circuit television. If you need them, just wave your hand and they will interrupt the treatment and come in to you immediately.
They return to the room after each treatment beam and move the machine to set up the next one. In some cases the radiographers do not enter the room until all treatment beams have been completed, and they control the movement of the machine
After a few minutes your treatment will be over for that day. This routine will go on each day until your course of treatment is finished.
The Effects of Radiotherapy
Any side effects will depend on several factors:
Side effects tend to become more evident as treatment goes on and will probably be at a peak just after the course has finished. The effects will start to subside a few weeks later. Side effects are carefully monitored during treatment and advice and medication will be available from the staff of the radiotherapy team. There are also precautions you, as the patient, can take to minimise these side effects. (See How to Help Yourself section).
Some people feel quite emotional, upset or anxious – this is normal. Fear of the unknown is common, so find out as much as possible about your treatment to reduce these feelings. Remember that you are not alone, there are people to help you, talk to your medical team, or family and friends.
Some of the side effects you may experience are as follows. You will be advised by your radiographers abour treatment side effects and how to minimise them.
How to help yourself during Radiotherapy
You are likely to receive written instructions on skin care and other precautions from your medical team whilst on radiotherapy. Be sure to follow these instructions carefully and always ask if there is anything worrying you regarding your treatment.
Further tips you may find useful are: