Radiotherapy uses high-energy rays to destroy the cancer cells, while doing as little harm as possible to normal cells.
Radiotherapy may be given to the anus and rectum after surgery. Nearby lymph nodes may also be treated. Radiotherapy given to this part of the body is called pelvic radiotherapy. The aim is to reduce the risk of the cancer coming back in that area.
The treatment is given as a series of short, daily sessions (called fractions) over a few weeks. You have treatment from a machine similar to a large x-ray machine. Radiotherapy only treats the area of the body that the rays are aimed at. It does not make you radioactive.
If the cancer has spread to other areas of the body, radiotherapy may be given to a specific area to control symptoms, such as bleeding or pain. In this case, you might only need a few days of treatment or just a single dose.
You may have side effects during your treatment. These usually disappear gradually over a few weeks or months after treatment finishes. Your radiotherapy team will let you know what to expect. Tell them about any side effects you have. There are often things that can help.
Some possible side effects are:
- dry, sore, itchy skin in the area being treated
- needing to pass urine more often
- diarrhoea or loose stools
- tiredness (fatigue).
We have more information about coping with the side effects of pelvic radiotherapy.