To Investigate The Prognosis Of Postmenopausal Breast Cancer Patients With Neoadjuvant Endocrine Therapy Based On Propensity Score Matching Method

Objective:To investigate the efficacy and prognosis of postmenopausal hormone receptor positive breast cancer patients receiving neoadjuvant endocrine therapy(NET)based on propensity score matching.Method: The clinicopathological data of 41 patients with postmenopausal hormone receptor-positive breast cancer who received Neoadjuvent endocrine therapy(NET)and 728 patients who received postoperative adjuvant endocrine therapy were retrospectively analyzed in the Department of Breast Surgery of the First Hospital of Bethune,Jilin University from January 2010 to March2019.Propensity score were tabulated using age,T stage,whether the lymph node metastases or not,clinical stage,the pathologic type,estrogen receptor(ER),progesterone receptor(PR),whether the human epidermal growth factor receptor2(HER-2)is expressed,molecular classification,histological classification,adjuvant chemotherapy or radiotherapy after surgery.The caliper matching method was used to match the patients receiving NET with the non-NET patients in a ratio of 1:2,and the caliper value was set at 0.05.After matching,31 patients with NET and 55 patients with non-NET were obtained,which were included in the study.Chi-square test and Fisher’s exact probability method were used to analyze the correlation between the clinicopathological characteristics and the duration of NET and the efficacy of NET in patients in the NET group,and the effects of the two treatment methods of NET or non-NET on the survival and prognosis of the patients were analyzed by using the single-factor Kaplan-Meier survival curve and Log-rank test.Result:Before PSM,the median follow-up time was 47 months(7-129 months).There were 7 cases of recurrence and metastasis(17.1%)and 4 cases of death(9.7%)in the NET group,and 35 cases of recurrence and metastasis(4.8%)and 33 cases of death(4.5%)in the Non-NET group.There was no significant difference in median age between the two groups(P=0.595).The number of T2-T3 patients in the NET group was significantly higher than that in the non-NET group(70.8% vs 32.2%,P<0.001),and lymph node metastasis was more common(87.8% vs 28.7%,P<0.001).Stage II-III patients were more common(92.7% vs 46%,P<0.001)and Ki-67>20% was more common(55% vs 32.2%,P=0.003)in NET group.The rates of breast-conserving surgery(BCS)in the two groups were 31.7% vs 19.9%(P=0.068),although the difference was not statistically significant,the BCS of the NET group was higher than that of the non-NET group.Among the patients in the NET group,1patient achieved clinical CR(2.4%),24 patients achieved PR(58.5%),16 patients achieved disease stability(39.1%),no disease progression(0%),and the overall response rate(ORR)was 60.9%,among which 1 patient achieved pathological complete response(p CR).In the NET group,the clinical remission rate after 6 months of treatment was significantly higher than that after 4-6 months of NET(76% vs37.5%,P=0.024),and the difference was statistically significant.Age of onset,histological classification,initial tumor size,axillary lymph node status,clinical stage,progesterone receptor and Ki-67 expression level,and whether Her-2 is expressed,molecular typing and histological grade were not significantly correlated with the clinical efficacy of NET(P>0.05).After PSM,the median follow-up time was 42.5 months(8-126 months),and a total of 86 patients were included,including31 patients(75.6%)in the NET group and 55 cases in non-NET group(7.6%).The5-year DFS of the NET group and the non-NET group were 82.7% vs 81.4%(P=0.334),and the 5-year OS were 89.1% vs 94.8%(P=0.202),respectively.There was no statistical difference between them.Conclusions:NET is mainly suitable for postmenopausal patients with hormone receptor positive breast cancer.After NET,the rate of breast-conserving surgery was increased by lowering stage.Prolonging the duration of NET can improve clinical remission rate.It was confirmed by the PSM method that the DFS and OS of postmenopausal breast cancer patients receiving preoperative neoadjuvant endocrine therapy or postoperative adjuvant endocrine therapy were the same under the same clinicopathological and postoperative combined treatment conditions.