新辅助化疗(NAC)后残余肿瘤细胞百分率(RTC)和病理完全缓解(pCR)是与乳腺癌(BC)良好预后相关的预后因素。然而，大多数患者只达到部分病理反应(pPR)，且RTC模式与预后之间没有明确的相关性。我们的目的是确定pCR的预测因素，并比较不同RTC模式的pCR或pPR患者的不同预后情况。我们从机构数据库中记录了基线和NAC后的人口学特征、临床病理特征、手术后数据、生存和复发状态。使用logistic回归模型进行多因素分析以确定pCR的独立预测因子。使用Kaplan-Meier方法进行无病生存期(DFS)、远处无病生存期(DDFS)和总生存期(OS)分析。在495名患者中，148名(29.9％)达到了pCR，347名(70.1％)有pPR，中位RTC为40％。多因素分析确定了3个独立的pCR预测因子: NAC前肿瘤分期(cT1-2 84.5％ vs cT3-4 15.5％)、BC亚型(HER2阳性54.7％ vs 三阴性29.8％ vs 延续型15.5％)和血管侵犯(缺席98.0％ vs 存在2.0％)。我们发现，具有pCR和RTC <40％的患者在DFS、DDFS和OS方面具有显着更长的生存时间；RTC <40％组和RTC ≥40％组之间在OS方面没有差异。NAC前肿瘤分期、BC亚型和血管侵犯是与pCR相关的重要而独立的因素。与pPR患者相比，具有pCR和RTC <40％的患者具有更长的DFS、DDFS和OS。版权所有©2023年作者。由Elsevier Ltd.出版。保留所有权利。

Residual tumor cellularity (RTC) and pathologic complete response (pCR) after neo-adjuvant chemotherapy (NAC) are prognostic factors associated with improved outcomes in breast cancer (BC). However, the majority of patients achieve partial pathologic response (pPR) and no clear correlation between RTC patterns and outcomes was described. Our aims were to define predictive factors for pCR and compare different outcomes of patients with pCR or pPR and with different RTC patterns.Baseline and post-NAC demographics, clinicopathological characteristics, post-operative data, survival and recurrence status were recorded from our institutional database. A multivariable analysis was performed using a logistic regression model to identify independent predictors of pCR. Disease-free survival (DFS), distant disease-free survival (DDFS), and overall survival (OS) analyses were performed using the Kaplan-Meier method.Overall, of the 495 patients analyzed, 148 (29.9%) achieved pCR, 347 (70.1%) had pPR, and the median RTC was 40%. Multivariable analysis identified 3 independent factors predictive of pCR: tumor stage before NAC (cT1-2 84.5% versus cT3-4 15.5%), BC sub-type (HER2-positive 54.7% versus triple-negative 29.8% versus luminal-like 15.5%), and vascular invasion (absence 98.0% versus presence 2.0%). We found statistically significant longer DFS, DDFS, and OS in patients with pCR and with RTC <40%; no difference was observed in terms of OS between RTC <40% and RTC ≥40% groups.Tumor stage before NAC, BC sub-type, and vascular invasion are significant and independent factors associated with pCR. Patients with pCR and with RTC <40% have longer DFS, DDFS, and OS compared with patients with pPR.Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.