Department of Medical Oncology of Cancer Center, West China Hospital, Sichuan University, Chengdu, China; Laboratory of Molecular Diagnosis of Cancer, Clinical Research Center for Breast, West China Hospital, Sichuan University, Chengdu, Sichuan, China.
Laboratory of Molecular Diagnosis of Cancer, Clinical Research Center for Breast, West China Hospital, Sichuan University, Chengdu, Sichuan, China; Department of Pathology, West China Hospital, Sichuan University, Chengdu, Sichuan, China.
Breast. 2022 Dec;66:89-96. doi: 10.1016/j.breast.2022.09.008. Epub 2022 Sep 30.
Little is known about the benefits of adjuvant endocrine therapy (ET) in low ER-positive breast cancer (1%-10%) patients. We analyzed the association between ET and breast cancer-specific survival (BCSS) in these patients with respect to the regimen and the duration of ET.
Patients were classified into three groups based on the regimen and duration of ET. The regimens included aromatase inhibitor (AI) monotherapy or sequential tamoxifen followed by an AI (AI/T + AI), or only tamoxifen and no ET. The duration of ET included 2-3 years and >3 years. Multivariate Cox regression analysis was employed to calculate the hazard ratios (HRs) with 95% confidence intervals (CIs).
Of the 10,696 patients diagnosed with breast cancer between 2010 and 2020, 407 women were identified with ER-low positive disease and met the inclusion criteria. During a median follow-up of 5.2 years, patients who received ET improved BCSS. Of them, those with AI/T + AI had increased BCSS compared to patients without ET, after adjusting for demographics and tumor characteristics, especially in ER-low/HER-2-positive breast cancer. After additional adjustment for treatment mode, the association maintained a similar trend. Patients who received >3 years of ET was associated with a better DFS. There was no significant difference in BCSS between patients with 2-3 years and >3 years of ET.
For ER-low patients, findings suggest that ET with AI/T + AI may be a reasonable treatment alternative. This effect should be assessed in randomized studies.
对于低雌激素受体阳性（1%-10%）乳腺癌患者，辅助内分泌治疗（ET）的获益知之甚少。我们分析了这些患者接受 ET 的方案和持续时间与乳腺癌特异性生存（BCSS）之间的关联。
根据 ET 的方案和持续时间将患者分为三组。方案包括芳香酶抑制剂（AI）单药治疗或序贯他莫昔芬后用 AI（AI/T+AI），或仅用他莫昔芬且不用 ET。ET 的持续时间包括 2-3 年和>3 年。采用多变量 Cox 回归分析计算风险比（HRs）及其 95%置信区间（CIs）。
在 2010 年至 2020 年期间诊断为乳腺癌的 10696 例患者中，有 407 例女性被诊断为 ER 低阳性疾病且符合纳入标准。在中位随访 5.2 年期间，接受 ET 的患者改善了 BCSS。调整人口统计学和肿瘤特征后，与未接受 ET 的患者相比，接受 AI/T+AI 的患者 BCSS 更高，尤其是在 ER 低/HER-2 阳性乳腺癌中。在进一步调整治疗模式后，该关联仍保持相似趋势。接受>3 年 ET 的患者与更好的无病生存期（DFS）相关。2-3 年和>3 年 ET 的患者在 BCSS 方面没有显著差异。
对于 ER 低患者，研究结果表明，AI/T+AI 的 ET 可能是一种合理的治疗选择。这一效果应在随机研究中进行评估。
