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

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.