Fluorouracil (5FU) and mitomycin C

Fluorouracil (5FU) and mitomycin C is the name of a chemotherapy drug combination. Next to each drug we have how you pronounce the drug name. 

• fluorouracil (floor-oh-yoor-uh-sil)
• mitomycin C (my-toe-my-sin C)

It is a treatment for anal, bladder, and vulva cancer.

You usually have it alongside a course of radiotherapy. This combined treatment is called chemoradiotherapy.

How does fluorouracil (5FU) and mitomycin C work?

These chemotherapy drugs destroy quickly dividing cells, such as cancer cells.

How do you have fluorouracil (5FU) and mitomycin C?

You have mitomycin and fluorouracil into your bloodstream. You may be able to have the infusions of 5FU at home if you have a central line.

To have the 5FU at home, you need to have the infusions through a small pump. You can keep the pump in a small bag, or a bag on a belt (like a bum bag). You’ll need to go back to the hospital to have the pump changed or taken down. Or sometimes a chemotherapy nurse may be able to do this at your home.

Into your bloodstream

You might have treatment through a long plastic tube that goes into a large vein in your chest. The tube stays in place throughout the course of treatment. This can be a:

• central line
• PICC line
• portacath

If you don’t have a central line

You might have treatment through a thin short tube (a cannula) that goes into a vein in your arm. You have a new cannula each time you have treatment.

Risk of tissue damage

When you are having this treatment through a cannula it could damage the tissue if it leaks out of the vein. This is called extravasation. This can happen anywhere along the vein that the drug is going into. It doesn’t happen very often. Tell your nurse straight away if you notice any changes such as swelling, redness, pain, burning, or a stinging feeling.

Your nurse will stop the drug treatment. And they will treat the area to relieve symptoms and reduce tissue damage. Contact your healthcare team if you develop any of these symptoms when you are at home.

How often do you have fluorouracil (5FU) and mitomycin C?

You usually have fluorouracil and mitomycin as a course of several cycles of treatment . Each cycle varies depending on what type of cancer you have.

Your doctor or nurse will tell you more about this.

Tests

You have blood tests before and during your treatment. They check your levels of blood cells and other substances in the blood. They also check how well your liver and kidneys are working.

Before starting treatment with fluorouracil (5FU) you have a blood test to check levels of an enzyme called dihydropyrimidine dehydrogenase (DPD). A low DPD level means you are more likely to have severe side effects from this chemotherapy, so you may start treatment with a lower amount (dose) of the drug or have a different treatment. Your doctor, nurse or pharmacist will talk to you about this.

What are the side effects of fluorouracil (5FU) and mitomycin C?

Side effects can vary from person to person. They also depend on what other treatments you're having. 

When to contact your team

Your doctor, nurse or pharmacist will go through the possible side effects. They will monitor you during treatment and check how you are at your appointments. Contact your advice line as soon as possible if:

• you have severe side effects 

• your side effects aren’t getting any better

• your side effects are getting worse

Early treatment can help manage side effects better. 

We haven't listed all the side effects here. Talk to your healthcare team if you have any new symptoms that you think might be a side effect of your treatment.

Remember it is very unlikely that you will have all of these side effects. But you might have some of them at the same time.

Common side effects

These side effects happen in more than 10 in 100 people (more than 10%). You might have one or more of them. They include:

Increased risk of infection 

Increased risk of getting an infection is due to a drop in white blood cells. Symptoms include a change in temperature, aching muscles, cough, headaches, feeling cold and shivery, pain or burning feeling when weeing, or generally feeling unwell. You might have other symptoms depending on where the infection is.

Infections can sometimes be life threatening. You should contact your advice line urgently if you think you have an infection. 

Breathlessness

You might be breathless and look pale due to a drop in red blood cells. This is called anaemia.

Bruising and bleeding

This is due to a drop in the number of platelets in your blood. These blood cells help the blood to clot when we cut ourselves. You may have nosebleeds or bleeding gums after brushing your teeth. Or you may have lots of tiny red spots or bruises on your arms or legs (known as petechiae).

Difficulty breathing and a cough

You might have a sudden feeling of tightness in your chest, difficulty catching your breath, wheezing and a cough. This is caused by spasms in the muscles of your airways. Contact your healthcare advice line or tell your doctor.

Feeling generally unwell

Speak to your doctor or nurse if you feel generally unwell after having this treatment.

Feeling weak

You might feel weak while having this treatment. 

Loss of appetite

You might lose your appetite for various reasons while having cancer treatment. Sickness, taste changes or tiredness can put you off food and drinks.

Feeling or being sick

Feeling or being sick is usually well controlled with anti sickness medicines. It might help to avoid fatty or fried foods, eat small meals and snacks and take regular sips of water. Relaxation techniques might also help.

It is important to take anti sickness medicines as prescribed even if you don’t feel sick. It is easier to prevent sickness rather than treat it once it has started.

A sore mouth

Mouth sores and ulcers can be painful. It helps to keep your mouth and teeth clean, drink plenty of fluids and avoid acidic foods such as lemons. Chewing gum can help to keep your mouth moist. Tell your doctor or nurse if you have ulcers.

Inflammation of the digestive system

This treatment may cause inflammation of the digestive system . This can cause pain and soreness.

It might include one or all of the following:

• the throat

• food pipe (oesophagitis)

• the tummy (stomach)

• the back passage (rectum)

You can have painkillers to reduce the soreness. Take them half an hour before meals to make eating easier. Your nurse, doctor or dietician will explain the best foods to have if you have any of these symptoms.

Diarrhoea

Contact your advice line if you have diarrhoea. For example, in one day you have 2 or more loose bowel movements than usual. If you have a stoma , you might have more output than normal. Your doctor may give you anti diarrhoea medicine to take home with you after treatment.

Try to eat small meals and snacks regularly. It’s best to try to have a healthy balanced diet if you can. You don’t necessarily need to stop eating foods that contain fibre. But if your diet is normally very high in fibre, it might help to cut back on high fibre foods such as beans, nuts, seeds, dried fruit, bran and raw vegetables. 

Drink plenty to try and replace the fluid lost. Aim for 8 to 10 glasses per day.

Heart problems

You might have heart rhythm changes picked up on a heart trace (ECG) . Less commonly it can cause chest pain. Other heart problems include changes in heart rhythm, a heart attack or problems with your heart muscle not working properly to pump blood around the body, but these are rare.  

Tell your doctor or nurse straight away if you have any chest pain.

Skin problems

Hand-foot syndrome or palmar plantar syndrome commonly happens with this treatment. This is were the skin on your hands and feet may become sore, red, or may peel. You may also have tingling, numbness, pain and dryness.

Other less common skin problems include a rash that becomes dry and itchy (contact dermatitis). Or a rash that comes with a fever, you generally not feeling well, and a headache (exanthema).

It’s rare but this treatment can also cause your skin to be more sensitive to light, you might have areas of skin that are lighter or darker.

Let your healthcare team know of any skin changes, they can help with the symptoms and what to do.

Hair loss

You could lose all your hair. This includes your eyelashes, eyebrows, underarms, legs and sometimes pubic hair. Your hair will usually grow back once treatment has finished but it is likely to be softer. It may grow back a different colour or be curlier than before. 

Occasional side effects

Between 1 and 10 out of every 100 people (between 1 and 10%) might develop kidneys problems. These are usually picked up on blood tests.

Rarely this treatment can cause small blood clots in the blood vessels inside the kidney (haemolytic uremic syndrome). Symptoms can include bloody diarrhoea, weakness, high temperature or being sick.

Rare side effects

These side effects happen in fewer than 1 in 100 people (fewer than 1%). You might have one or more of them. They include:

• a serious reaction to an infection (sepsis), signs can include feeling very unwell, not passing urine, being sick, a very high or very low temperature or shivering - contact your advice line straight away if you have any of these symptoms

• confusion

• an allergic reaction that can cause a rash, shortness of breath, redness or swelling of the face and dizziness

• nail problems including thickening, pain, changes in colour of the nail and nail bed

• feeling happy and excited (euphoria)

• shaking and trembling, stiffness and slow movement (symptoms of Parkinson's disease)

• headaches

• dizziness

• low blood pressure that can make you feel faint and dizzy

• changes to how your liver works that can cause yellowing of the skin and whites of your eyes - you have regular blood tests to check this

• feeling very sleepy and sleeping for longer periods of time

• a blood disorder called haemolytic anaemia where the red blood cells are destroyed faster than they can be made

• eye problems such as watery eyes, changes to your vision, rapid eye movement side to side, blocked tear ducts, or sensitivity to light

• a high temperature (fever)

Other side effects

If you have side effects that aren't listed on this page, you can look at the individual drug pages:

• mitomycin C
• fluorouracil (5FU)

Coping with side effects

We have more information about side effects and tips on how to cope with them.

What else do you need to know?

Other medicines, foods and drink

Cancer drugs can interact with medicines, herbal products, and some food and drinks. We are unable to list all the possible interactions that may happen. An example is grapefruit or grapefruit juice which can increase the side effects of certain drugs.

Tell your healthcare team about any medicines you are taking. This includes vitamins, herbal supplements and over the counter remedies. Also let them know about any other medical conditions or allergies you may have.

Pregnancy and contraception

This treatment may harm a baby developing in the womb. It is important not to become pregnant or get someone pregnant while you're having treatment and for at least 6 months afterwards.

Talk to your doctor or nurse about effective contraception before starting treatment. Let them know straight away if you or your partner become pregnant while having treatment. 

Loss of fertility

You may not be able to become pregnant or get someone pregnant after treatment with these drugs. Talk to your doctor before starting treatment if you think you may want to have a baby in the future.

Men might be able to store sperm before starting treatment. And women might be able to store eggs or ovarian tissue. But these services are not available in every hospital, so you would need to ask your doctor about this.    

Breastfeeding

It is not known whether these drugs come through into the breast milk. Doctors usually advise that you don’t breastfeed during this treatment.

Other conditions 

If you are having tests or treatment for anything else, always mention your cancer treatment. For example, if you are visiting your dentist.

Immunisations

Don’t have immunisations with live vaccines while you’re having treatment and for up to 12 months afterwards. The length of time depends on the treatment you are having. Ask your doctor or pharmacist how long you should avoid live vaccinations.

In the UK, live vaccines include rubella, mumps, measles, BCG, yellow fever and one of the shingles vaccines called Zostavax.

You can have:

• other vaccines, but they might not give you as much protection as usual
• the flu vaccine (as an injection)
• the coronavirus (COVID-19) vaccine - talk to your doctor or pharmacist about the best time to have it in relation to your cancer treatment

Members of your household who are aged 5 years or over are also able to have the COVID-19 vaccine. This is to help lower your risk of getting COVID-19 while having cancer treatment and until your immune system recovers from treatment.

Contact with others who have had immunisations - You can be in contact with other people who have had live vaccines as injections. Avoid close contact with people who have recently had live vaccines taken by mouth (oral vaccines) such as the oral typhoid vaccine. Sometimes people who have had the live shingles vaccine can get a shingles type rash. If this happens they should keep the area covered.

If your immune system is severely weakened, you should avoid contact with children who have had the flu vaccine as a nasal spray as this is a live vaccine. This is for 2 weeks following their vaccination.

Babies have the live rotavirus vaccine. The virus is in the baby’s poo for about 2 weeks and could make you ill if your immunity is low. Get someone else to change their nappies during this time if you can. If this isn't possible, wash your hands well after changing their nappy.

More information about this treatment

For further information about this treatment and possible side effects go to the electronic Medicines Compendium (eMC) website. You can find the patient information leaflet on this website.

You can report any side effect you have to the Medicines Health and Regulatory Authority (MHRA) as part of their Yellow Card Scheme.