Bari Shahla, Boulware David, Li Jiannong, Loftus Loretta, Soyano Muller Aixa, Jameel Zena, Khong Hung, Czerniecki Brian J, Costa Ricardo L B
Department of Hematology/Oncology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA.
Department of Biostatistics, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA.
Breast Cancer (Dove Med Press). 2022 Aug 6;14:199-210. doi: 10.2147/BCTT.S371975. eCollection 2022.
Estrogen receptor-positive (ER) breast cancer (BC) is a heterogeneous disease, and there is an ongoing debate regarding the optimal cut point for clinically relevant ER expression. We used a real-world database to assess the prognostic and predictive values of lower ER expression levels on treatment outcomes with endocrine therapy.
We used a nationwide electronic health record database. Descriptive statistics were used to evaluate the association between ER expression, tumor characteristics, and treatment patterns among patients with early-stage BC. We used Kaplan-Meier survival curves to estimate recurrence-free survival (RFS) and overall survival (OS). We assessed associations between an alternative ER expression-level cut point and clinical outcomes.
Among 4697 patients with early-stage HER2-negative BC, 83 (2.04%) had ER-low BC (ER expression, 1-9.99%) and 36 (0.88%) had ER-intermediate BC (10-19.9%). ER-low tumors were associated with higher tumor grade, larger size, and higher axillary tumor burden than ER-high tumors (≥20% ER expression). African Americans had a higher prevalence of both triple-negative BC (TNBC) and ER-low BC than ER-high BC. Patients with ER-low and ER-intermediate tumors had survival outcomes similar to patients with TNBC and worse survival outcomes than patients with ER-high tumors ( < 0.001). Tumors with <20% ER expression were associated with worse outcomes.
In our cohort, patients with BCs with ER expression levels <20% had poor clinical outcomes similar to those of patients with TNBC.
雌激素受体阳性（ER）乳腺癌（BC）是一种异质性疾病，关于临床相关ER表达的最佳切点一直存在争议。我们使用一个真实世界数据库来评估较低ER表达水平对内分泌治疗疗效的预后和预测价值。
我们使用了一个全国性的电子健康记录数据库。描述性统计用于评估早期BC患者中ER表达、肿瘤特征和治疗模式之间的关联。我们使用Kaplan-Meier生存曲线来估计无复发生存期（RFS）和总生存期（OS）。我们评估了另一种ER表达水平切点与临床结局之间的关联。
在4697例早期HER2阴性BC患者中，83例（2.04%）为ER低表达BC（ER表达为1-9.99%），36例（0.88%）为ER中等表达BC（10-19.9%）。与ER高表达肿瘤（ER表达≥20%）相比，ER低表达肿瘤与更高的肿瘤分级、更大的肿瘤大小和更高的腋窝肿瘤负荷相关。非裔美国人三阴乳腺癌（TNBC）和ER低表达BC的患病率均高于ER高表达BC。ER低表达和ER中等表达肿瘤患者的生存结局与TNBC患者相似，且比ER高表达肿瘤患者的生存结局更差（P<0.001）。ER表达<20%的肿瘤与更差的结局相关。
在我们的队列中，ER表达水平<20%的BC患者的临床结局较差，与TNBC患者相似。
