CMF

CMF is the name of a chemotherapy combination used to treat breast cancer. Doctors most often use it to try to stop breast cancer from coming back after surgery and radiotherapy. This is called adjuvant therapy. CMF is

• C = Cyclophosphamide
• M = Methotrexate
• F = Fluorouracil (5FU)

You can click on the links to find out about the side effects of each individual drug.

In the UK, it is most common to have CMF as injections and tablets. You have each treatment over 3 or 4 weeks. You take cyclophosphamide tablets every day for the first 2 weeks and have injections of methotrexate and 5FU on the 1st and 8th days of each 3 or 4 week cycle. 

It is very important that you take tablets according to the instructions your doctor or pharmacist gives you. For example, whether you have a full or empty stomach can affect how much of a drug gets into your bloodstream. You should take the right dose, not more or less. And never stop taking a cancer drug without talking to your specialist first. Keep tablets in tightly closed containers and out of the reach of children. Return any unused tablets to the pharmacy.

Instead of having CMF as described above you may have all the drugs by injection every 3 or 4 weeks. All 3 drugs are injected on the 1st and 8th day of each 3 or 4 week cycle.

However you have the treatment, it is most common to have 4 to 6 cycles of CMF. CMF is often given as E-CMF where you have 4 cycles of epirubicin and 4 cycles of CMF. 

The side effects of a combination of drugs are usually a mixture of the side effects of each individual drug. You may get some of the side effects. The combination of drugs may increase or decrease your chance of getting each side effect. Or it may change the severity. The side effects associated with CMF are listed below. Use the links (underlined) to find out more about each side effect. Where there is no link please see our cancer drug side effects section, or use the search box at the top of the page.

More than 10 in every 100 people have one or more of the side effects listed below.

A temporary drop in the number of blood cells made by the bone marrow, causing

• An increased risk of getting an infection from a drop in white blood cells – it is harder to fight infections and you can become very ill. You may have headaches, aching muscles, a cough, sore throat, pain passing urine or feel cold and shivery
• Tiredness and breathlessness due to a drop in red blood cells (anaemia) – you may need a blood transfusion
• Bruising more easily due to a drop in platelets – you may have nosebleeds, bleeding gums after brushing your teeth, or lots of tiny red spots or bruises on your arms or legs (known as petechia)

Some of these side effects can be life threatening, particularly infections. You should contact your treatment centre if you have any of these effects. Your doctor will check your blood counts regularly to see how well your bone marrow is working.

Other common side effects include

• Fatigue (tiredness) during and after treatment – most people find their energy levels are back to normal from 6 months to a year after their treatment finishes
• Feeling or being sick – this can be a problem for some people taking cyclophosphamide tablets. Try taking anti sickness medicines at least an hour before you take your cyclophosphamide
• Loss of appetite
• Hair loss or thinning – some women only have mild thinning but others have more and some may have complete hair loss
• Diarrhoea
• A sore mouth or mouth ulcers 
• Metallic taste or loss of taste – this may only be on the days when you are having your drugs and should get better when your treatment finishes
• Sore eyes – they may feel as if they have grit in them
• Blurred vision or watery eyes
• CMF may have a harmful effect on a developing baby so it is advised not to become pregnant or father a child if you are having these drugs. You need to talk about contraception with your doctor or nurse before having the treatment
• Women may stop having periods (amenorrhoea) but this may only be temporary
• Loss of fertility – you may not be able to get pregnant after having this treatment. It is important to talk to your doctor about your fertility before starting treatment

Between 1 and 10 in every 100 people have one or more of these.

• Skin changes – your skin may darken or you may have an itchy rash
• Your skin may become sensitive to sunlight so use a high factor sun cream and cover up when you go out
• Nail changes – your nails may become ridged, or darken. They may become brittle and chip or break easily
• Coughing or breathlessness
• Liver changes that are very mild and unlikely to cause symptoms – the liver will almost certainly go back to normal when the treatment ends but you will have regular blood tests to check how well your liver is working
• Kidney changes that are mild and unlikely to cause symptoms may occur – they will almost certainly go back to normal when treatment finishes but you will have regular blood tests to check how well your kidneys are working

Fewer than 1 in 100 people have these.

• An allergic reaction when you are having methotrexate can cause an itchy rash, a high temperature and shivering, redness of the face, dizziness, a headache or breathlessness – tell your chemotherapy nurse if you have any of these symptoms
• Burning, stinging or pain on passing urine (cystitis) – if you see blood in your urine contact your doctor or nurse straight away
• Heart problems – there is a very small risk of angina (chest pain) or a heart attack
• Fluid retention
• Confusion or unsteadiness
• There is a small risk of developing another cancer years after finishing the treatment

The side effects above may be mild or more severe. A side effect may get better or worse through your course of treatment, or more side effects may develop as the course goes on. This depends on

• How many times you've had the drug before
• Your general health
• The amount of the drug you have (the dose)
• Other drugs you are having

Talk to your doctor, pharmacist or nurse about all your side effects so that they can help you manage them. Your nurse will give you a contact number to ring if you have any questions or problems. Your treatment team can give you advice or reassure you so if in doubt, call them.

Tell your doctor about any other medicines you are taking, including vitamins, herbal supplements and other over the counter remedies – some drugs can react together.

You should not have immunisations with live vaccines while you are having this treatment or for at least 6 months afterwards. In the UK, live vaccines include rubella, mumps, measles (usually given together as MMR), BCG and yellow fever. You can have other vaccines, but they may not give you as much protection as usual until your immune system has fully recovered.

It is safe for you to be in contact with other people who've had live vaccines as injections. There can be problems with oral vaccines, but not many people in the UK have oral vaccines now. So there is usually no problem in being with any baby or child who has recently had any vaccination in the UK. You might need to make sure that you aren't in contact with anyone who has had oral polio, cholera or typhoid vaccination recently, particularly if you live abroad.