Variations in dose and dose intensity of adjuvant CMF chemotherapy for breast cancer throughout the UK

Cyclophosphamide, methotrexate and 5-fluorouracil (CMF) is a commonly prescribed regimen for the adjuvant treatment of early breast cancer in the UK and in other countries with a high incidence of breast carcinoma. A number of variations in dose and scheduling of these drugs have been reported in the literature, with all of these being recognized under the generic term 'CMF'. To investigate the extent of differences in CMF regimens used for the adjuvant treatment of early breast cancer we sent a postal questionnaire to all consultant medical and clinical oncologists in the UK seeking details of their practice. CMF drug doses were then converted into dose intensity parameters for comparison. The results showed a wide variation in the number of CMF schedules (n = 36) and CMF dose intensities (n = 33) used. The potential consequences of such variation and the evidence for and against dose intensity as an important parameter in the adjuvant treatment of early breast cancer are discussed.