This study evaluated whether doxorubicin and cyclophosphamide are superior to cyclophosphamide, methotrexate and 5-fluorouracil as adjuvant chemotherapy in breast cancer patients. Between July 1976 and December 2004, 1045 breast cancer patients received adjuvant chemotherapy at the Radiotherapy Unit of the University of florence. 927 were administered i.v. CMF (cyclophosphamide 600 mg/m(2), methotrexate 40 mg/m(2) and 5-fluorouracil 600 mg/m(2) on days 1 and 8, repeated every 28 days for a total of six cycles) and 118 i.v. DC (doxorubicin 60 mg/m(2) and cyclophosphamide 600 mg/m(2) on day 1 repeated every 21 days for a total of four cycles). All patients underwent adjuvant radiotherapy as well. The survival analysis, stratified according to treatment, did not show any significant difference in metastasis occurrence between the two groups (log rank test p=0.42). According to multivariate analysis four parameters emerged as independent prognostic factors for distant metastases in patients treated with the Cmf regimen: pt (p=0.0005), number of positive axillary lymph nodes (p=<0.0001), tamoxifen use (p=0.0109) and local relapses (p=<0.0001). Only number of positive axillary lymph nodes and local relapses were significant predictors of metastases occurrence according to multivariate analysis in the DC group, 17 and p=0.028, respectively. No significant difference between the two regimens was observed with regards to number of involved nodes. DC and CMF produced similar outcome in breast cancer patients.