Having radiotherapy for anal cancer

You have radiotherapy in the hospital radiotherapy department. You are usually treated once a day from Monday to Friday, with a rest over the weekend. If you are having the radiotherapy treatment with chemotherapy, you will have it for between 4 and 6 weeks. Each treatment lasts a few minutes.

Radiotherapy treatment is carefully planned. On your first visit, you lie under a large machine called a simulator. Simulators take either normal X-rays or a CT scan. Below is a picture of someone on the simulator, taken from the radiographer's control room. As you can see, all you usually have to do is lie down. At times, the radiographer may ask you to keep very still.

The doctor uses the X-rays or scans to work out exactly where to give the treatment so that it

• Kills the most cancer cells
• Misses as much healthy body tissue as possible

During the planning session, marks may be made on your skin. You will also have a few pinprick tattoos made during planning. The radiographers use these to line up the machine accurately and make sure the treatment area is exactly right each time you have treatment.

External beam radiotherapy doesn't hurt. You won't be able to feel it, but you need to lie very still for the few minutes that you have your treatment. You usually have treatment every weekday (Monday to Friday) for about 5 to 6 weeks. Below is a picture of a treatment room, showing the radiotherapy machine.

External beam radiotherapy doesn't make you radioactive. It is perfectly safe to be with other people, including children, throughout your course of treatment.

If you are having internal radiotherapy (brachytherapy), you will have radioactive wires put into the area of the tumour while under a general anaesthetic. You will have an x-ray to check that they are in the correct place. The treatment usually takes a few days. You will need to stay in hospital and will be in a special, protected room of your own and children and pregnant women won’t be able to visit youbecause the wires release some radioactivity. When you finish your treatment, the doctor takes the wires out under either local or general anaesthetic. After they’ve gone, radioactivity is no longer given out, so you will be able to go home. There will not be any radiation in your body, so you won't be any danger to anyone else.

Some studies are looking at giving higher doses of internal radiotherapy (brachytherapy) over shorter periods of time. So you might have 2 short sessions of radiotherapy a day for up to 5 days. Apart from these times, you will not have any radiation in your body.

You can find out more about internal radiotherapy in our main radiotherapy section.