Chemotherapy for anal cancer

Chemotherapy uses drugs to treat cancer and it is a common treatment for anal cancer. It is often given with radiotherapy (called chemoradiation).

Anal cancer chemotherapy

Chemotherapy uses anti-cancer (cytotoxic) drugs to destroy cancer cells. These drugs disrupt the way cancer cells grow and divide, but they also affect normal cells. The chemotherapy drugs are usually given by injection into a vein (intravenously) or as tablets.

For people with anal cancer, chemotherapy is usually given in combination with radiotherapy (chemoradiation). Chemotherapy can also be used on its own if the cancer has spread to other parts of the body. It may help control the cancer and improve symptoms.

The most commonly used chemotherapy drugs for anal cancer are:

Other drugs that may be used are:

How chemotherapy is given

Most chemotherapy drugs for anal cancer are given by injection into a vein (intravenously). The chemotherapy goes directly into your blood and is carried to all areas of your body.

It can be given through one of the following:

  • A central line – This is a long, thin tube inserted into a vein in your chest. It stays in until you have finished your course of chemotherapy.
  • A PICC line (peripherally inserted central venous catheter) – This is a long, thin, flexible tube inserted into a vein in the arm. It stays in until you have finished your course of chemotherapy.
  • A cannula – This is a short, thin tube put into a vein in the back of your hand or arm. It is taken out before you go home.

Sometimes chemotherapy is given continuously through a small, portable pump attached to your central or PICC line. It gives a controlled amount of the drug into your bloodstream over a set period of time. This means that you can go home with the pump and spend less time in hospital.

You usually have chemotherapy as an outpatient. After the treatment, you usually have a rest period of a few weeks. This lets your body recover from any side effects of the treatment.

The treatment and rest period make up a cycle of treatment. Your cancer doctor or specialist nurse will explain how many cycles of treatment you need.

We have more information about having chemotherapy.

Getting support

Macmillan is here to support you. If you would like to talk, you can:

Possible side effects of chemotherapy

Chemotherapy can sometimes cause side effects. But if the cancer is causing symptoms, chemotherapy can also make you feel better by relieving them. Most people have some side effects from chemotherapy. Your cancer doctor or nurse will tell you more about what to expect.

Tell them about any side effects you have, as they can usually be well controlled with medicines.

We describe the common side effects below. Although they can be hard to cope with, they usually slowly disappear when your treatment finishes.

Risk of infection

This treatment can reduce the number of white blood cells in your blood. These cells fight infection. If the number of white blood cells is low, you are more likely to get an infection. A low white blood cell count is called neutropenia.

If you have an infection, it is important to treat it as soon as possible. Contact the hospital straight away on the 24-hour contact number you have if:

  • your temperature goes over 37.5°C (99.5°F)
  • you suddenly feel unwell, even with a normal temperature
  • you have symptoms of an infection.

Symptoms of an infection include:

  • feeling shivery
  • a sore throat
  • a cough
  • diarrhoea
  • needing to pass urine often.

It is important to follow any specific advice your cancer treatment team gives you.

The number of white blood cells will usually return to normal before your next treatment. You will have a blood test before having more treatment. If your white blood cell count is low, your doctor may delay your treatment for a short time.

Bruising and bleeding

This treatment can reduce the number of platelets in your blood. Platelets are cells that help the blood to clot. Tell your doctor if you have any bruising or bleeding that you cannot explain. This includes:

  • nosebleeds
  • bleeding gums
  • tiny red or purple spots on the skin that may look like a rash.

Some people may need a drip to give them extra platelets. This is called a platelet transfusion.

Anaemia (low number of red blood cells)

This treatment can reduce the number of red blood cells in your blood. These cells carry oxygen around the body. If the number of red blood cells is low, you may be tired and breathless.

Tell your doctor or nurse if you feel like this. If you are very anaemic, you may need a drip to give you extra red blood cells. This is called a blood transfusion.

Tiredness (fatigue)

Feeling tired is a common side effect. Tiredness is often worse towards the end of treatment and for some weeks after it has finished. Try to pace yourself and plan your day so you have time to rest. Gentle exercise, like short walks, can give you more energy. If you feel sleepy, do not drive or operate machinery.

Feeling sick

You may feel sick in the first few days after treatment. Your doctor will give you anti-sickness drugs to help prevent or control sickness. Take the drugs exactly as your nurse or pharmacist tells you. It is easier to prevent sickness than to treat it after it has started.

If you feel sick, take small sips of fluids and eat small amounts often. If you continue to feel sick, or if you vomit more than once in 24 hours, contact the hospital as soon as possible. They will give you advice and may change the anti-sickness drug to one that works better for you.


Some chemotherapy drugs can cause diarrhoea. This can happen in the first few days of treatment. But it usually happens between treatment cycles. If you have this side effect, tell your nurse or doctor as they can give you medicine to help.

If you still have diarrhoea after 24 hours, it is important to contact the hospital on the telephone numbers you have been given and speak to a doctor or nurse. If you have a stoma, your stoma care nurse can also give you advice and support.

Make sure you drink at least 2 litres (3½ pints) of fluid each day to replace the fluid you are losing. Eat less fibre, such as cereals, raw fruits and vegetables, until the diarrhoea improves.

Sometimes diarrhoea is more severe. If you have diarrhoea more than 4 times in a day or at night, it is important to contact the hospital straight away and speak to a doctor or nurse.

If you are taking capecitabine and your diarrhoea does not get better, tell your doctor or nurse. Sometimes you may have to stop taking capecitabine until the diarrhoea gets better.

You may need to go to hospital to have fluids through a drip (infusion), or you may need antibiotics.

Sore mouth

You may get a sore mouth or mouth ulcers. This can make you more likely to get a mouth infection. Use a soft toothbrush to clean your teeth or dentures in the morning, at night and after meals.

If your mouth is sore:

  • tell your nurse or doctor – they can give you a mouthwash or medicines to help
  • try to drink plenty of fluids
  • avoid alcohol, tobacco, and foods that irritate your mouth.

Sore hands and feet

This is sometimes called palmar-plantar or hand-foot syndrome. It can be caused by capecitabine (Xeloda®) or 5FU. It gets better when treatment ends.

Your doctor or nurse may prescribe creams or tablets to improve the symptoms. Using non-perfumed moisturising creams can help relieve symptoms.

It can help to keep your hands and feet cool and to avoid tight-fitting socks, shoes and gloves.


Some cancer treatments can affect whether you can get pregnant or make someone pregnant. If you are worried about this, it is important to talk with your doctor before you start treatment.


Your doctor will advise you not to get pregnant or make someone pregnant while having this treatment. The drugs may harm a developing baby.

It is important to use contraception during your treatment and for a while after treatment finishes. Your doctor, nurse or pharmacist can tell you more about this.


If you have sex during a course of chemotherapy, you need to use a condom. This is to protect your partner in case there is any chemotherapy in semen or vaginal fluids.

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 Chief 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.

Date reviewed

Reviewed: 30 April 2020
Next review: 30 April 2023

This content is currently being reviewed. New information will be coming soon.

Trusted Information Creator - Patient Information Forum
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