Department of Breast and Medical Oncology, National Cancer Center Hospital, 5-1-1, Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan.
Department of Breast Medical Oncology, National Center for Global Health and Medicine, 1-21-1 Toyama, Shinjuku-ku, Tokyo, 162-8655, Japan.
Breast Cancer. 2019 Jul;26(4):492-498. doi: 10.1007/s12282-019-00949-4. Epub 2019 Feb 8.
Trastuzumab emtansine (T-DM1) has been approved since 2013 for patients with human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer (MBC) who had received trastuzumab (Tmab) and taxane. However, no clinical trial has evaluated the efficacy of T-DM1 in those who have previously received pertuzumab (Pmab). This study aimed to compare the efficacy of T-DM1 between patients who had received Tmab and Pmab and those who had received Tmab only in Japanese population.
We identified all patients with HER2-positive MBC who received T-DM1 between April 1, 2014 and February 28, 2017 in our institution. The patients were divided into the Tmab group (i.e., those who received only Tmab before T-DM1 treatment) and the Tmab/Pmab group (i.e., those who received Tmab and Pmab before T-DM1 treatment), and progression-free survival (PFS) and best response were compared between the two groups.
A total of 42 patients were enrolled for outcome analysis. The median follow-up period was 4.8 months, and the median number of prior chemotherapy regimens for metastatic disease before T-DM1 was 1 (range 1-2) in the Tmab/Pmab group and 2 (range 0-6) in the Tmab group. The median PFS was 2.8 months in the Tmab/Pmab group (95% confidence interval [CI] 1.7-4.8 months) and 7.8 months in the Tmab group (95% CI 5.5-15.9 months) (p = 0.0030). The best response was lower in the Tmab/Pmab group (11.1% vs. 25.0%).
Patients with HER2-positive MBC who received Tmab and Pmab treatment before T-DM1 have fewer benefits from T-DM1.
曲妥珠单抗-美坦新偶联物（T-DM1）自 2013 年以来已被批准用于接受曲妥珠单抗（Tmab）和紫杉烷治疗的人表皮生长因子受体 2（HER2）阳性转移性乳腺癌（MBC）患者。然而，尚无临床试验评估 T-DM1 在先前接受过帕妥珠单抗（Pmab）治疗的患者中的疗效。本研究旨在比较 T-DM1 在接受过 Tmab 和 Pmab 治疗的患者与仅接受过 Tmab 治疗的患者中的疗效。
我们在我院确定了所有在 2014 年 4 月 1 日至 2017 年 2 月 28 日期间接受 T-DM1 治疗的 HER2 阳性 MBC 患者。将患者分为 Tmab 组（仅在 T-DM1 治疗前接受 Tmab）和 Tmab/Pmab 组（在 T-DM1 治疗前接受 Tmab 和 Pmab），并比较两组之间的无进展生存期（PFS）和最佳反应。
共有 42 例患者入组进行结局分析。中位随访时间为 4.8 个月，在 Tmab/Pmab 组中，T-DM1 治疗前转移性疾病的中位化疗方案数为 1（范围 1-2），在 Tmab 组中为 2（范围 0-6）。在 Tmab/Pmab 组中，PFS 的中位数为 2.8 个月（95%置信区间 [CI] 1.7-4.8 个月），在 Tmab 组中为 7.8 个月（95% CI 5.5-15.9 个月）（p=0.0030）。T-DM1 治疗前接受 Tmab 和 Pmab 治疗的患者的最佳反应率较低（11.1%比 25.0%）。
接受过 Tmab 和 Pmab 治疗的 HER2 阳性 MBC 患者从 T-DM1 中获益较少。
