RESUMEN
BACKGROUND: A regimen of docetaxel, doxorubicin, and cyclophosphamide (TAC) is superior to a regimen of fluorouracil, doxorubicin, and cyclophosphamide (FAC) when used as adjuvant therapy in women with node-positive breast cancer. The value of taxanes in the treatment of node-negative disease has not been determined. METHODS: We randomly assigned 1060 women with axillary-node-negative breast cancer and at least one high-risk factor for recurrence (according to the 1998 St. Gallen criteria) to treatment with TAC or FAC every 3 weeks for six cycles after surgery. The primary end point was disease-free survival after at least 5 years of follow-up. Secondary end points included overall survival and toxicity. RESULTS: At a median follow-up of 77 months, the proportion of patients alive and disease-free was higher among the 539 women in the TAC group (87.8%) than among the 521 women in the FAC group (81.8%), representing a 32% reduction in the risk of recurrence with TAC (hazard ratio, 0.68; 95% confidence interval [CI], 0.49 to 0.93; P=0.01 by the log-rank test). This benefit was consistent, regardless of hormone-receptor status, menopausal status, or number of high-risk factors. The difference in survival rates (TAC, 95.2%; FAC, 93.5%) was not significant (hazard ratio, 0.76; 95% CI, 0.45 to 1.26); however, the number of events was small (TAC, 26; FAC, 34). Rates of grade 3 or 4 adverse events were 28.2% with TAC and 17.0% with FAC (P<0.001). Toxicity associated with TAC was diminished when primary prophylaxis with granulocyte colony-stimulating factor was provided. CONCLUSIONS: As compared with adjuvant FAC, adjuvant TAC improved the rate of disease-free survival among women with high-risk, node-negative breast cancer. (Funded by GEICAM and Sanofi-Aventis; ClinicalTrials.gov number, NCT00121992.).