Comparison of Docetaxel, Doxorubicin and Cyclophosphamide (TAC) with 5-Fluorouracil, Doxorubicin and Cyclophosphamide (FAC) Neoadjuvant Chemotherapy in Locally Advanced Breast Cancer: A Phase III Clinical Trial

Abstract

Background: The present study aimed to compare the rates of complete clinical and pathologic response to docetaxel, doxorubicin and cyclophosphamide (TAC) vs. 5-fluorouracil, doxorubicin and cyclophosphamide (FAC) as neoadjuvant chemotherapy in women with locally advanced breast cancer. Methods: One hundred women with pathologically confirmed newly diagnosed locally advanced (T3-T4 or N2-N3) breast cancer were randomly assigned to receive a median of four cycles of either 5-fluorouracil (600 mg/m2), doxorubicin (60 mg/m2) and cyclophosphamide (600 mg/m2) every three weeks or docetaxel (75 mg/m2), doxorubicin (50 mg/m2) and cyclophosphamide (500 mg/m2) every three weeks followed by modified radical mastectomy. Complete clinical and pathologic response rates and toxicity were the primary and secondary outcome measures of the study.Results: Median age for all patients was 43.4 years (range 25-63 years). Patients in the TAC arm achieved a higher clinical (16%) response rate than those in the FAC arm (4%, P=0.046). The pathologic response rate was also higher in the TAC arm compared to the FAC arm [TAC (20%) vs. FAC (6%), P=0.037]. Estrogen receptor- negative status correlated with a higher clinical [TAC (19%) vs. FAC (4%), P=0.032] and pathologic [TAC (23%) vs. FAC (4%), P=0.011)] response rate in both arms. All patients generally tolerated treatment well, and treatment-related toxicities were manageable.Conclusion: Combined treatment with TAC led to higher rates of complete clinical and pathologic response with acceptable toxicity compared to FAC in patients with locally advanced breast cancer. However, further follow-up is needed to translate this response into improvements in survival.