Abstract:Objective To investigate the therapeutic effect and related influencing factors of neoadjuvant chemotherapy (NAC) for hormone receptor positive/human epidermal growth factor receptor 2 negative (HR⁺/HER^2-) breast cancer,so as to provide reference for clinical individualized decision-making. Methods A retrospective analysis was performed on the clinicopathological data of 131 patients with HR⁺/HER^2-breast cancer received NAC for the first time from 2015 to 2019.The associations of curative effect with age,histological grade,tumor size,lymph node status,estrogen receptor (ER),progesterone receptor (PR),Ki-67,chemotherapy regimen and chemotherapy cycle were analyzed by using rank sum test and chi-square test.The influencing factors of curative effect were analyzed by dichotomous logistic regression,and the best cut-off values of related factors were calculated by ROC.Kappa test was used to analyze the consistency between Miller -Payne classification and RECIST (response evaluation criteria in solid tumors) criteria. Results The pathological complete remission (pCR) rate was 3.6%,and the effective rate was 63.4% in 131 patients.Multivariate analysis showed that high expression of ER (OR=1.048,P<0.01),low expression of Ki-67 (OR=0.935,P<0.01),and few chemotherapy cycles (OR=0.426,P<0.05) were independent risk factors of NAC efficacy.ROC curve showed that the area under the curve for ER,Ki-67 expression and chemotherapy cycle to predict the efficacy of NAC were 0.774,0.780,0.821,and the best cut-off values were 65.0%,22.5%,and 6 cycles,respectively. The consistency test suggested that the consistency between Miller-Payne classification and RECIST criteria was poor (Kappa=0.335). Conclusions pCR of NAC for HR⁺/HER^2-breast cancer is low,and high ER expression (≥65.0%),low Ki-67 expression(≤22.5%) and chemotherapy cycles ≤6 are the independent risk factors of curative effect.The consistency between Miller-Payne classification and RECIST criteria is poor after NAC.