Division of Medical Oncology, Department of Internal Medicine, Cerrahpaşa Faculty of Medicine, İstanbul University-Cerrahpaşa, İstanbul, Turkey.
Department of Medical Oncology, Faculty of Medicine, Recep Tayyip Erdoğan University, Rize, Turkey.
BMC Cancer. 2024 Oct 24;24(1):1311. doi: 10.1186/s12885-024-13064-1.
The HER-2 status of breast cancer (BC) has been classified as negative or positive for a long time. Given the efficacy of novel anti-HER2-targeted antibody drug conjugates (ADCs) in HER2-low BC, a distinct subgroup of HER2-low tumors has emerged within BC. The biology and prognostic impact of HER2-low expression are not yet well defined, and inconsistent results were reported. This study aims to evaluate the impact of low HER-2 status on the response to neoadjuvant chemotherapy (NACT) and disease- free survival (DFS) rates.
We retrospectively analyzed BC patients treated with NACT from 2017 to 2023 in two cancer centers. HER2-negative patients were included. HER-2 low status was defined by IHC + 1 or + 2/ISH non-amplified, and HER2-zero was defined by IHC 0. Pathological complete response (pCR) rates and DFS between HER2-low and HER2-zero populations were compared.
170 patients were identified. 122 (72%) of these patients were HER2- zero BC, whereas 48 (28%) were HER2-low BC. Overall, pCR was achieved in 35 (20.5%) patients. Of these, pCR was observed in 30 patients (44.6%) from the HER2- zero group, compared to 5 patients (10.4%) from the HER2-low group (p = 0.046), but significance was lost in multivariate analysis. Among the hormone receptor (HR) positive subtype, pCR was achieved 19.8% of HER2-zero tumors and 7.5% of HER2-low tumors (p = 0.08). For HR-negative subtype 34.1% HER2-zero tumors had pCR and 25% of the HER2-low tumors had pCR (p = 0.614). There was no association between DFS and HER2-low status.
Our study indicates that HER2-low status had no impact on pCR or DFS.
长期以来，乳腺癌（BC）的 HER-2 状态被分为阴性或阳性。鉴于新型抗 HER2 靶向抗体药物偶联物（ADC）在 HER2 低 BC 中的疗效，BC 中出现了一个明确的 HER2 低肿瘤亚组。HER2 低表达的生物学和预后影响尚未得到很好的定义，并且报告的结果不一致。本研究旨在评估低 HER-2 状态对新辅助化疗（NACT）反应和无病生存（DFS）率的影响。
我们回顾性分析了 2017 年至 2023 年在两个癌症中心接受 NACT 治疗的 BC 患者。纳入 HER2 阴性患者。HER2 低状态定义为 IHC+1 或+2/ISH 非扩增，HER2 零状态定义为 IHC0。比较 HER2 低和 HER2 零人群的病理完全缓解（pCR）率和 DFS。
共 170 例患者入选。其中 122 例（72%）为 HER2 零 BC，48 例（28%）为 HER2 低 BC。总体而言，35 例（20.5%）患者达到 pCR。其中，HER2 零组 30 例（44.6%）患者达到 pCR，而 HER2 低组 5 例（10.4%）患者达到 pCR（p=0.046），但多变量分析失去意义。在激素受体（HR）阳性亚组中，HER2 零肿瘤的 pCR 率为 19.8%，HER2 低肿瘤的 pCR 率为 7.5%（p=0.08）。在 HR 阴性亚组中，34.1%的 HER2 零肿瘤有 pCR，25%的 HER2 低肿瘤有 pCR（p=0.614）。DFS 与 HER2 低状态之间无关联。
我们的研究表明，HER2 低状态对 pCR 或 DFS 没有影响。
