Comparison of Docetaxel, Doxorubicin and Cyclophosphamide (TAC) with ۵-Fluorouracil, Doxorubicin and Cyclophosphamide (FAC) Neoadjuvant Chemotherapy in Locally Advanced Breast Cancer: A Phase III Clinical Trial

Background: The present study aimed to compare the rates of complete clinical and pathologic response to docetaxel, doxorubicin and cyclophosphamide (TAC) vs. ۵-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 (T۳-T۴ or N۲-N۳) breast cancer were randomly assigned to receive a median of four cycles of either ۵-fluorouracil (۶۰۰ mg/m۲), doxorubicin (۶۰ mg/m۲) and cyclophosphamide (۶۰۰ mg/m۲) every three weeks or docetaxel (۷۵ mg/m۲), doxorubicin (۵۰ mg/m۲) and cyclophosphamide (۵۰۰ mg/m۲) 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 ۴۳.۴ years (range ۲۵-۶۳ years). Patients in the TAC arm achieved a higher clinical (۱۶%) response rate than those in the FAC arm (۴%, P=۰.۰۴۶). The pathologic response rate was also higher in the TAC arm compared to the FAC arm [TAC (۲۰%) vs. FAC (۶%), P=۰.۰۳۷]. Estrogen receptor- negative status correlated with a higher clinical [TAC (۱۹%) vs. FAC (۴%), P=۰.۰۳۲] and pathologic [TAC (۲۳%) vs. FAC (۴%), P=۰.۰۱۱)] 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.