ERRB2 阳性乳腺癌患者的标准辅助治疗是化疗加 1 年曲妥珠单抗。较短的曲妥珠单抗给药持续时间可提高心脏安全性，但需要更多关于其对生存的影响的信息。为了比较曲妥珠单抗给药 9 周与 1 年与相同辅助化疗后的生存结果。这项对开放式的事后二次分析标签、多中心、非劣效性设计随机临床试验纳入了 18 岁或以上患有早期 ERBB2 阳性、腋窝淋巴结阴性或腋窝淋巴结阳性乳腺癌的女性，她们于 2008 年 1 月 3 日至 2014 年 12 月 16 日期间入组。 7 个欧洲国家的 65 个中心。当前的探索性分析是在最后一位入组患者于 2022 年 12 月完成最后一次预定就诊时获得最大可达到的随访数据后进行的。化疗包括 3 个周期的多西紫杉醇，每 3 周一次，然后是 3 个周期的氟尿嘧啶，表柔比星和环磷酰胺，间隔 3 周。两组均给予曲妥珠单抗并同时给予多西他赛 9 周。在9周组中，化疗后不再给予曲妥珠单抗，而在1年组中，化疗后继续给予曲妥珠单抗以完成1年的给药。主要目标是无病生存（DFS）。遥远的 DFS 和 OS 是次要目标。使用 Kaplan-Meier 方法和对数秩检验或单变量 Cox 比例风险回归比较组间生存率。在分析的 2174 名女性中，中位年龄为 56 岁（IQR，48-64 岁）。中位随访时间为 8.1 年（IQR，8.0-8.9 年）；发生 357 起 DFS 事件和 176 人死亡。与曲妥珠单抗 1 年相比，曲妥珠单抗 9 周的 DFS 较短（风险比 [HR]，1.36；90% CI，1.14-1.62）； 1 年组的 10 年 DFS 为 80.3%，而 9 周组为 78.6%。 9 周组和 1 年组的 5 年和 10 年 OS 率相当（分别为 95.0% vs 95.9% 和 89.1% vs 88.2%；所有时间点的 HR，1.20；90% CI，0.94 -1.54）。在多变量分析中，与 1 年治疗相比，9 周治疗与较短的 DFS 相关（复发或死亡的 HR，1.36；95% CI，1.10-1.68；P = .005），但组间没有差异OS（HR，1.22；95% CI，0.90-1.64；P = .20）。只有 4 名患者 (0.2%) 死于心脏原因。 在这项随机临床试验的二次分析中，1 年与 9 周辅助曲妥珠单抗与接受化疗的 ERRB2 阳性乳腺癌患者的 DFS 改善相关，但各组之间的 OS 没有显着差异。ClinicalTrials.gov 标识符：NCT00593697。

The standard adjuvant treatment for patients with ERRB2-positive breast cancer is chemotherapy plus 1 year of trastuzumab. Shorter durations of trastuzumab administration improve cardiac safety, but more information is needed about their effect on survival.To compare survival outcomes after 9-week vs 1-year administration of trastuzumab with the same adjuvant chemotherapy.This post hoc secondary analysis of an open-label, multicenter, noninferiority-design randomized clinical trial included women aged 18 years or older with early ERBB2-positive, axillary node-negative or axillary node-positive breast cancer who were enrolled from January 3, 2008, to December 16, 2014, at 65 centers in 7 European countries. The current exploratory analysis was conducted after achieving the maximum attainable follow-up data when the last patient enrolled had completed the last scheduled visit in December 2022.Chemotherapy consisted of 3 cycles of docetaxel administered at 3-week intervals followed by 3 cycles of fluorouracil, epirubicin, and cyclophosphamide at 3-week intervals. Trastuzumab was administered in both groups for 9 weeks concomitantly with docetaxel. In the 9-week group, no further trastuzumab was administered after chemotherapy, whereas in the 1-year group, trastuzumab was continued after chemotherapy to complete 1 year of administration.The primary objective was disease-free survival (DFS). Distant DFS and OS were secondary objectives. Survival between groups was compared using the Kaplan-Meier method and log-rank test or univariable Cox proportional hazards regression.Among the 2174 women analyzed, median age was 56 years (IQR, 48-64 years). The median follow-up time was 8.1 years (IQR, 8.0-8.9 years); 357 DFS events and 176 deaths occurred. Trastuzumab for 9 weeks was associated with shorter DFS compared with trastuzumab for 1 year (hazard ratio [HR], 1.36; 90% CI, 1.14-1.62); 10-year DFS was 80.3% in the 1-year group vs 78.6% in the 9-week group. The 5-year and 10-year OS rates were comparable between the 9-week and 1-year groups (95.0% vs 95.9% and 89.1% vs 88.2%, respectively; HR for all time points, 1.20; 90% CI, 0.94-1.54). In multivariable analyses, 9-week treatment was associated with shorter DFS compared with 1-year treatment (HR for recurrence or death, 1.36; 95% CI, 1.10-1.68; P = .005), but there was no between-group difference in OS (HR, 1.22; 95% CI, 0.90-1.64; P = .20). Only 4 patients (0.2%) died of a cardiac cause.In this secondary analysis of a randomized clinical trial, 1-year vs 9-week adjuvant trastuzumab was associated with improved DFS among patients with ERRB2-positive breast cancer receiving chemotherapy, but there was no significant difference in OS between the groups.ClinicalTrials.gov Identifier: NCT00593697.