Chemoradiotherapy for mouth and oropharyngeal cancer

Chemoradiotherapy means having chemotherapy and radiotherapy treatment together.

Chemotherapy uses anti cancer (cytotoxic) drugs to destroy cancer cells. The drugs circulate throughout the body in the bloodstream.

Radiotherapy uses high energy x-rays to destroy cancer cells.

You might have chemoradiotherapy as your main treatment. Or you might have it after surgery to lower the risk of your cancer coming back.

When you have it

Early mouth and oropharyngeal cancer cancer

You might have chemoradiotherapy after surgery if there is a high risk of your cancer coming back

Locally advanced mouth and oropharyngeal cancer

Locally advanced cancers have grown into the surrounding tissues or lymph nodes. 

You might have chemoradiotherapy on its own as your main treatment for a locally advanced cancer. 

Or you might have chemoradiotherapy after surgery. This is called adjuvant treatment.

How does chemoradiotherapy work?

Chemotherapy drugs can make cells more sensitive to radiotherapy. This helps radiotherapy to kill cancer cells. Researchers have found that chemoradiotherapy works better than radiotherapy alone for some people with mouth and oropharyngeal cancer.

How you have it

Your exact treatment plan depends on your situation.

Your radiotherapy might last for about 6 to 7 weeks. You usually have it daily for 5 days every week, Monday to Friday. Your chemotherapy may be every 3 to 4 weeks. Or it might be weekly. 

Chemoradiotherapy can be quite a tough treatment. It can cause damage to some healthy cells at the same time. This might cause side effects. You will need some tests to check you are well enough to cope with it.  


You usually have treatment in the chemotherapy day unit or you might need to stay in hospital for a day or more.

The most common drugs used for mouth and oropharyngeal cancer are cisplatin and fluorouracil (5FU).


Before you begin treatment, the radiotherapy team works out how much radiation you need. They divide it into a number of smaller treatments. They call each treatment a fraction. This is called radiotherapy planning.

You might also have a mask made. The radiographers use this to help keep you in the correct position for the treatment.

Photograph of a mesh plastic mask used for radiotherapy for cancer of the head and neck and brain

Side effects

You will get some side effects from your treatment. These are the same kinds of side effects you get from radiotherapy or chemotherapy alone. But when you have both treatments together some of the side effects can be more severe.

Everyone is different and the side effects vary from person to person. You might not have all of the effects mentioned by your doctor or radiographer. Side effects depend on the type of chemotherapy you have. They also depend on the radiotherapy treatment area.

The side effects gradually get worse during the treatment. They can continue to get worse after your treatment ends. But most of the side effects begin to improve after 1 or 2 weeks.

Always let your doctor, nurse or radiographer know about any side effects you have so that they can help.

Sore mouth and throat

You are likely to get a very sore mouth and throat. This often starts after about 2 weeks of treatment. You may only manage soft food and liquid supplements. Some people find that their mouth is so sore that it is too difficult to swallow. If this happens, you are likely to need a feeding tube so that you can get enough liquid and calories.

You also have painkillers. You might need a strong painkiller such as morphine to help make your mouth more comfortable.

When you have a very sore mouth and throat, you must be very careful about infection. Try to keep your mouth clean and follow the advice of your nurse and dentist.

Contact the hospital at the first sign of infection – particularly a change in temperature, chills, or a cough. 

Dry mouth

A dry mouth can make eating and talking uncomfortable. Your doctor can prescribe artificial moisteners for your mouth if it is a problem for you. People who have a dry mouth often find it helps to sip water regularly and carry a bottle of water with them all the time.

Swelling (lymphoedema)

You are at risk of getting swelling called lymphoedema in your neck or face if the lymph nodes in your neck are in the treatment area. Lymphoedema is pronounced lim-fo-dee-ma.

Lymph fluid is in all body tissues. It comes from the tiny blood vessels into the body tissues. Usually, it drains back into the bloodstream through channels called lymph vessels. These are part of the lymphatic system.

A build up of lymph fluid in an area of the body can happen if lymph drainage channels or lymph nodes are blocked, removed or damaged.

Lymphoedema in the head or neck can also cause symptoms inside your mouth and throat. For example, swelling of your tongue and other parts of your mouth.

Tell your doctor or nurse straight away if you:

  • have any swelling or a feeling of fullness or pressure
  • find it difficult to swallow
  • have changes in your voice

Lymphoedema is easier to control if treated early. It's important that you are referred to a lymphoedema specialist if you have signs of swelling. This is usually a nurse or physiotherapist.

Increased risk of infection

An increased risk of getting an infection is due to a drop in white blood cells. The chemotherapy affects cells, such as white blood cells, in your bone marrow. Symptoms of an infection include a change in temperature, aching muscles, headaches, feeling cold and shivery and generally unwell.

You might have other symptoms depending on where the infection is.

Contact your doctor or nurse immediately if you have signs of infection, including a temperature above 37.5C or below 36C, or generally feeling unwell. Infections can make you very unwell very quickly.

Sore skin in the head and neck area

Your skin might go red or darker in the treatment area. You might also get slight redness or darkening on the other side of your head and neck. This is where the radiotherapy beams leave the body. 

The red or darker areas can feel sore. Your radiographers will give you creams to soothe your skin. The soreness usually goes away within 2 to 4 weeks of ending the treatment. But your skin might always be slightly darker in that area.

Tell the radiotherapy staff if you notice any skin changes.

Difficulty swallowing

During and after treatment, you might have difficulty swallowing.

You may see a speech and language therapist (SLT) before you start treatment if this is likely to affect your swallowing. An SLT can assess your swallowing during and after treatment. They can teach exercises to support you with swallowing difficulties. And they work with a dietitian if you are finding it difficult to eat.

You can have feeds through a nasogastric tube that goes up your nose and down into your stomach. Or you can have a PEG tube (percutaneous endoscopic gastrostomy tube) that goes through the skin into your stomach. Your nurse or dietician will tell you more about this if you need to have one. They will also show you and your relatives how to give the feeds. 

Tips for eating and drinking:

  • Drink about 3 litres of water a day while having treatment.
  • Eat soft foods.
  • Eat slowly and avoid eating late in the day.
  • Drink plenty during and after meals to soften your food.
  • Eat small amounts often rather than big meals.
  • Try different foods to find out which are easiest to swallow.
  • You can have high calorie drinks to boost your calorie intake if you need them.
  • You might need to have liquid food into your vein or through a tube into your nose or stomach if you can’t eat enough.

Tiredness and weakness

You might feel tired during your treatment. It tends to get worse as the treatment goes on. You might also feel weak and lack energy. Rest when you need to.

Tiredness can carry on for some weeks after the treatment has ended. But it usually improves gradually.

Various things can help you to reduce tiredness and cope with it, such as exercise. Some research has shown that taking gentle exercise can give you more energy. It's important to balance exercise with resting.

Feeling or being sick

Sickness may be worse a few hours after the chemotherapy. Anti sickness injections and tablets can control it. Tell your doctor or nurse if you feel sick. You might need to try different anti sickness medicines to find one that works.


  • Avoid eating or preparing food when you feel sick.
  • Avoid hot fried foods, fatty foods or foods with a strong smell.
  • Eat several small meals and snacks each day.
  • Relaxation techniques help control sickness for some people.
  • Ginger can help – try it as crystallised stem ginger, ginger tea or ginger ale.
  • Try fizzy drinks.
  • Sip high calorie drinks if you can’t eat.


If you smoke, your doctor will advise you to stop. Smoking during treatment can make the side effects worse. 

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  • Definitive chemoradiotherapy in patients with squamous cell cancers of the head and neck - results from an unselected cohort of the clinical cooperation group “Personalized Radiotherapy in Head and Neck Cancer

    Lar Schüttrumpf and others

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    The Journal of Laryngology & Otology, 2016. Volume 130,  Supplement 2

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Last reviewed: 
31 May 2022
Next review due: 
31 May 2025

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