Due Asbjørn, Berg Tobias, Jensen Maj-Britt, Yammeni Sophie, Volmer Lone, Brems-Eskildsen Anne Sofie, Andersen Klaus Kaae, Rana Saeeda, Knoop Ann, Kümler Iben
Danish Breast Cancer Group, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark.
Department of Oncology, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark.
Acta Oncol. 2023 Feb;62(2):126-133. doi: 10.1080/0284186X.2023.2176257. Epub 2023 Mar 17.
Current guidelines in HER2-positive metastatic breast cancer (mBC) recommend the combination of trastuzumab and a chemotherapeutic agent for 3rd line or later treatments. This study aims to describe the treatment of HER2-positive mBC in 3rd line or later after previous treatment with T-DM1 for mBC in a real-world setting.
This observational population-based study included all women diagnosed with HER2-positive mBC in Denmark, previously treated with T-DM1 in the metastatic setting. Patients were included on the date of progression leading to initiation of 3rd line treatment if the patient had received T-DM1 in 1st or 2nd line. If the patient received T-DM1 in 3rd line or later the inclusion was based on the date of progression on T-DM1. The primary end points were overall survival (OS) and progression-free survival (PFS).
The study included 272 women with a mean age of 59 (27-86) and a median of 3 (2-11) treatment lines prior to inclusion. At index, all patients had received T-DM1 and 167 (62%) patients had received pertuzumab in the metastatic setting. During follow-up 183 patients received chemotherapy. Of these patients, 120 received chemotherapy combined with trastuzumab, 50 received chemotherapy combined with other HER2-targeted therapy, and 13 received chemotherapy as monotherapy. The remaining 89 patients received either HER2-targeted monotherapy (41), endocrine therapy (31), experimental treatment (10), or no treatment (7). Median PFS was 5.5 months (95% CI, 4.8-6.5) and median OS was 18.5 months (95% CI, 16.2-21.3).
In this real-world study, we found that patients were treated with a wide variety of anti-cancer agents with modest efficacy. However, patients in this study did not have access to newer therapies like tucatinib and T-DXd.
人表皮生长因子受体2（HER2）阳性转移性乳腺癌（mBC）的现行指南推荐曲妥珠单抗与化疗药物联合用于三线及后续治疗。本研究旨在描述在真实世界中，HER2阳性mBC患者在先前接受mBC的曲妥珠单抗-美坦新偶联物（T-DM1）治疗后的三线及后续治疗情况。
这项基于人群的观察性研究纳入了丹麦所有诊断为HER2阳性mBC且先前在转移阶段接受过T-DM1治疗的女性患者。如果患者在一线或二线接受过T-DM1治疗，则在导致三线治疗开始的疾病进展日期纳入研究。如果患者在三线或更晚接受T-DM1治疗，则根据T-DM1治疗的疾病进展日期纳入。主要终点为总生存期（OS）和无进展生存期（PFS）。
该研究纳入了272名女性，平均年龄59岁（27 - 86岁），纳入前的治疗线数中位数为3（2 - 11）。在入组时，所有患者均接受过T-DM1治疗，167名（62%）患者在转移阶段接受过帕妥珠单抗治疗。在随访期间，183名患者接受了化疗。其中，120名患者接受了化疗联合曲妥珠单抗治疗，50名患者接受了化疗联合其他HER2靶向治疗，13名患者接受了单纯化疗。其余89名患者接受了HER2靶向单药治疗（41名）、内分泌治疗（31名）、试验性治疗（10名）或未接受治疗（7名）。中位PFS为5.5个月（95%置信区间，4.8 - 6.5），中位OS为18.5个月（95%置信区间，16.2 - 21.3）。
在这项真实世界研究中，我们发现患者接受了多种抗癌药物治疗，疗效一般。然而，本研究中的患者无法使用图卡替尼和曲妥珠单抗重组冻干粉注射剂（T-DXd）等新型疗法。
