Analysis of neoadjuvant chemotherapy for breast cancer: A 20-year retrospective analysis of patients of a single institution

Background: Neoadjuvant chemotherapy has been widely applied in operable breast cancer patients. This study aim to identify the predictive factors of overall survival(OS) and recurrence free survival (RFS) in breast cancer patients who received NAC from a single Chinese institution . Patients and Methods There were 646 patients recruited in this study. All the patients were treated at department of Surgical Oncology, Sir Run Run Shaw Hospital between February 25, 1999 and August 22, 2018. The relevant clinicopathological and follow-up data were collected retrospectively. RFS and OS were assessed using the Kaplan-Meier method. Multivariate Cox proportional hazards model was also employed.Multi-variate logistic regression model was simulated to predict pathologic complete response (pCR) . Results In total, 126 patients (19.5%) achieved pCR during NAC. The 5-year OS was 92.6% and 75.3% in patients with and without pCR, respectively (P<0.001). The 5-year RFS was 93.4% and 71.2%, respectively (P<0.001). No difference was detected among molecular subtypes of 5-year RFS in patients obtained pCR. Factors independently predicting RFS were HER2-positive subtype (hazard ratio(HR), 1.793; P=0.006), triple-negative breast cancer (TNBC) (HR,1.895; P=0.002), Ki-67>25 (HR, 2.363; P=0.044), lymph node involvement after NAC(HR,3.639; P<0.001), pCR (HR, 0.375;P=0.004), and clinical stage III (HR,2.918; P=0.014). Multi-variate logistic regression model was simulated to predict the pCR rate after NAC, according to clinical stage, molecular subtype, ki-67, LVSI, treatment period and histology. In the ROC curve analysis, the AUC of the nomogram was 0.734(95%CI,0.867–12.867). Conclusions Following NAC, we found that pCR positively correlated with prognosis and the molecular subtype was a prognostic factor.