Cmar_a_284638 1517..1527

*These authors contributed equally to this work Purpose: To retrospectively analyze the efficacy and toxicity of epirubicin plus cyclophosphamide followed by docetaxel (EC-D) and epirubicin plus cyclophosphamide followed by paclitaxel (EC-P) efficacy as neoadjuvant chemotherapy regiments by pathological complete response (pCR) in this study. Methods: In total, 455 patients diagnosed with breast cancer who received NAC from January 2014 to January 2019 were enrolled. Of which, 109 patients received EC-D (E: 90, C: 600, D: 80, all in mg/m2) and 346 were treated with EC-P (E: 90, C: 600, D: 175, all in mg/m2). Efficacy of NAC regimens was evaluated by pCR, and the toxicity was studied. Chi-squared test was used at p=0.05. Results: In EC-D, 11 patients received ypT0/isN0, and 6 of them got ypT0N0. Analogously, 67 patients receiving received EC-P obtained ypT0/isN0, and 43 people of them acquired ypT0N0. The rate of pCR in EC-P was higher than EC-D. Patients with ER (-), PR (-), Her-2 (+) and high Ki-67 index were easier to were more likely to acquire pCR. Two pCRs were described, the pCR of NAC differed according to the definition. In terms of side effects, there was no significant difference in platelet and urea, but the decrease of hemoglobin and creatinine levels after EC-P treatment was more significant than that after EC-D treatment. Conclusion: The efficacy of EC-P is better than EC-D if pCR is to be determined as a surrogate end-point for prognosis. The patients with anemia or renal insufficiency who need to receive NAC should choose EC-D.