Radiotherapy for anal cancer

Radiotherapy can be used to cure or control cancer in the pelvic area. This type of treatment is called pelvic radiotherapy and it is used to treat a number of different cancers.

Pelvic radiotherapy can be given externally or internally. Some people may have a combination of both types. Radiotherapy given externally is the most common way for anal cancer.

Side effects of pelvic radiotherapy depend on different factors including the dose of radiotherapy and whether it’s external or internal.

If you have other types of treatment such as surgery or chemotherapy, this can also affect the side effects you might have. Radiotherapy used together with chemotherapy is the most common treatment for anal cancer.

If you are having any side effects, talk to your cancer doctor, specialist nurse or radiographer. They can give you advice and treatment to help you cope.

What is pelvic radiotherapy?

Radiotherapy treats cancer by using high-energy rays to destroy the cancer cells, while doing as little harm as possible to healthy cells.

Radiotherapy can either be given from outside the body (externally) or from inside the body (internally). Some people are treated with a combination of both methods.


Pelvic radiotherapy for anal cancer

Radiotherapy, usually in combination with chemotherapy, is the most common treatment for anal cancer. The chemotherapy makes the cancer cells more sensitive to radiotherapy. This treatment is called chemoradiation.

You may have radiotherapy on its own if your doctors feel that you aren’t fit enough to have chemoradiotherapy. It’s sometimes used on its own to relieve symptoms of advanced anal cancer.

Radiotherapy given externally is the most common way of giving radiotherapy for anal cancer.


Side effects of pelvic radiotherapy

Radiotherapy destroys cancer cells in the treated area, but it can also have an effect on some of the surrounding normal tissue. 

Radiotherapy affects people in different ways, so it’s difficult to predict exactly how you will react to it. The side effects you have will depend on different factors. These include the dose of radiotherapy given and whether it’s external or internal radiotherapy. 

If you also have other types of cancer treatment, such as surgery or chemotherapy, this can affect the side effects you have. Having chemotherapy at the same time as radiotherapy (called chemoradiotherapy) may cause more severe side effects.

Your cancer specialist, specialist nurse or radiographer will explain the most likely side effects in your situation. Let them know about any concerns or questions you have. They’ll be able to explain how side effects can be treated and give advice on how to cope with them. 

Most side effects are temporary and start a week or two into the treatment. They may continue to get worse for a couple of weeks after treatment, before they begin to get better. Side effects usually improve gradually over the next few weeks or more.

Occasionally, some side effects don’t completely go away, or side effects develop months or years later as a result of the radiotherapy. These are called long-term or late effects.

Back to Radiotherapy explained

Who might I meet?

You will meet many different specialists before, during and after radiotherapy treatment.