CMF
Meaning of CMF: The combination that first proved chemotherapy after surgery could stop breast cancer returning, now largely overtaken by newer schedules.
Definition of CMF
CMF is a chemotherapy combination for breast cancer made up of cyclophosphamide, methotrexate and fluorouracil, given in repeated cycles. It was the first drug combination shown to lower the chance of breast cancer coming back when given after surgery. Anthracycline and taxane regimens have since displaced it for most purposes, although it is still used where those drugs are unsuitable.
What do the three drugs do?
Each attacks a different step in copying DNA, which is why the three together achieve what none manages alone. Combining agents with separate mechanisms also makes it harder for a tumor to become resistant to all of them at once, the principle that governs almost every chemotherapy combination built since.
| Letter | Drug | How it acts |
|---|---|---|
| C | Cyclophosphamide | Attaches to DNA so the strands cannot separate to be copied |
| M | Methotrexate | Blocks folate processing, starving the cell of DNA building blocks |
| F | Fluorouracil | A counterfeit building block that jams DNA and RNA assembly |
Why did it matter?
Before this regimen, chemotherapy was reserved for disease that had already spread and was visible. Giving it to people whose tumor had been removed and who appeared free of cancer was a genuine departure, resting on the idea that stray cells too few to see were already lodged elsewhere and were what caused relapse years later. Trials showed fewer recurrences and longer survival, which established adjuvant treatment as a principle and changed the management of many other cancers. Describing it as an agent under investigation, as older reference entries still do, gets the history exactly backward.
Where does it stand now?
Anthracycline and taxane schedules generally outperform it against breast cancer, so it is no longer the default. What keeps it in use is its side effect profile rather than its strength. It carries no risk to heart muscle, which anthracyclines do, and none of the nerve damage that taxanes cause, so it remains relevant for people with existing heart disease or neuropathy. Hair thinning is usual rather than complete loss. Against that, the schedule stretches over more months than the newer alternatives, and methotrexate leaves the body through the kidneys, so reduced kidney function raises its toxicity.
Also known as
Used in a sentence
Adjuvant CMF was given following breast-conserving surgery.
Good to know
CMF is an established regimen rather than an experimental one, and its practical distinction from anthracycline and taxane schedules is the absence of heart muscle and nerve toxicity, at the cost of a longer course.