Anal cancer chemoradiation

Chemoradiation is when chemotherapy and radiotherapy are given at the same time. It is sometimes called chemoradiotherapy. It is often the main treatment for anal cancer.

We have separate information on radiotherapy and chemotherapy for anal cancer, which includes detailed information about the individual treatments and their side effects.

Why chemoradiation is given

Chemotherapy drugs can make cancer cells more sensitive to radiotherapy. This can help the radiotherapy to work better. Having both treatments often works better than having either treatment on its own.

Chemoradiation has a better chance of curing anal cancer than surgery. It also means you may avoid having a stoma.

How chemoradiation is given

You usually have chemoradiation as an outpatient.

A common treatment plan involves having 4 to 6 weeks of radiotherapy and two cycles of chemotherapy. The chemotherapy drugs usually given are fluorouracil (5FU) and mitomycin.

In the first week of treatment, you start chemotherapy and have your first radiotherapy treatment.

You have radiotherapy Monday to Friday, for 4 to 6 weeks.

4 weeks after you started treatment, you have a second cycle of chemotherapy.

You usually have the chemotherapy into a vein (intravenously). You may have fluorouracil through a portable chemotherapy pump, which you take home. Or you may have a drug called capecitabine instead of fluorouracil, which you take as a tablet.

We have more information about how how chemotherapy is given.

Side effects

Having chemotherapy and radiotherapy together can make the side effects of treatment worse. Your cancer doctor or specialist nurse will give you more information about chemoradiation and the possible side effects. You may have the following side effects:

Tell your doctor, specialist nurse or radiographer about your side effects. They can help you find ways to cope with them.

About our information



  • Reviewers

    This information has been written, revised and edited by Macmillan Cancer Support’s Cancer Information Development team. It has been reviewed by expert medical and health professionals and people living with cancer. It has been approved by Senior Medical Editor, Professor Tim Iveson, Consultant Medical Oncologist.

    Our cancer information has been awarded the PIF TICK. Created by the Patient Information Forum, this quality mark shows we meet PIF’s 10 criteria for trustworthy health information.

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