CMF: Cyclophosphamide, methotrexate, and fluorouracil

CMF (cyclophosphamide, methotrexate, and fluorouracil) is a chemotherapy regimen used to treat early-stage and metastatic breast cancer.

CMF is a combination of three chemotherapy medicines:

• Cyclophosphamide (Cytoxan)
• Methotrexate
• Fluorouracil (5-FU)

How CMF works

Each CMF medicine treats the cancer cells in a different way:

• Cyclophosphamide stops cancer cells from reproducing.
• Methotrexate and fluorouracil stop cells from making and fixing DNA. This causes the cells to die when they try to divide.

Who gets CMF

CMF has been found to be effective for:

• Early-stage breast cancer, whether or not it has spread to nearby lymph nodes
• Metastatic breast cancer

In early-stage breast cancer, CMF is used as adjuvant therapy (after surgery). CMF is the only chemotherapy regimen that can be given at the same time as radiation therapy, although this is not commonly done.

In metastatic breast cancer, CMF is used on an ongoing basis as long as the treatment effectively controls the cancer.

You and your doctor will discuss the best chemotherapy treatment for your situation.

How CMF is given

CMF can be given in different ways.

To treat early-stage breast cancer after surgery (adjuvant treatment):

• All three medicines can be given together by vein (intravenous infusion or through a chemotherapy port) on the first day of treatment. This cycle is usually repeated every 21 days for a total of 8 cycles (about 6 months of treatment).
• One medicine is taken as a pill and the others are given by vein:
  • Cyclophosphamide is taken by mouth as a daily pill for 14 days.
  • Methotrexate and fluorouracil are given together, by vein, on days 1 and 8 of this 14-day period.
  • After finishing the cyclophosphamide pills, there is a 14-day rest period, making a total of 28 days in this first cycle of treatment.
  • This 28-day cycle is usually repeated a total of six times (six cycles in about 6 months).

To treat metastatic breast cancer, all three medicines are usually given intravenously every 3 weeks for as long as it is working to control the cancer.

Side effects and things to remember

Different medicines have different side effects. You may not have every side effect related to each medicine of the combination therapy. Common side effects of CMF include:

• Low blood counts (including white blood cells, red blood cells, and platelets)
• Risk of infection
• Bruising or bleeding
• Nausea and vomiting
• Loss of appetite
• Mouth sores
• Diarrhea
• Fatigue
• Eye problems
• Bladder irritation
• Hair loss
• Menopausal symptoms

Less common side effects include:

• Nail and skin changes
• Heart problems
• Kidney and liver problems

Before starting CMF, be sure to tell your doctor about any medicines you are taking — including vitamins, herbal supplements, and over-the-counter medicines — to make sure they won’t interfere with your chemotherapy treatment.

You will need a blood test before you start treatment. Contact your doctor right away if you develop a fever or other symptoms of an infection such as a sore throat, cough or diarrhea.

You should avoid becoming pregnant while you are receiving CMF. Tell your doctor right away if you become pregnant or may be pregnant while you are getting treatment.

Be sure to talk to your doctor, pharmacist or nurse about all your side effects so that they can help you manage them. You can also go to our section on Side effects for more information.