Influence of radiotherapy on the dose of adjuvant chemotherapy in early breast cancer

399 patients with early breast cancer were randomly allocated to treatment by either modified radical mastectomy or lumpectomy and radiotherapy. 169 had histologically involved axillary nodes and were randomised to receive either adjuvant cytotoxic chemotherapy (76 patients) or no systemic adjuvant treatment (93 patients). Chemotherapy comprised a combination of oral cyclophosphamide and intravenous methotrexate and 5-fluorouracil (CMF) for 12 cycles over one year.