Zhang Mengqi, Li Mingxiao, Zhou Shihan, Jiang Mingxia, Liu Jiaxuan, Yang Xue, Qin Ling, Abudureheiyimu Nilupai, Shi Xiuqing, Li Lixi, Li Fengjuan, Guan Xiuwen, Ma Fei, Xu Binghe, Li Qiao
Department of Medical Oncology, Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100021, China.
Oncologist. 2026 Feb 5;31(3). doi: 10.1093/oncolo/oyag032.
Neoadjuvant treatment for hormone receptor (HR)-positive breast cancer remains limited, particularly for tumors that are insensitive to neoadjuvant chemotherapy. This study aims to compare the efficacy of neoadjuvant endocrine therapy combined with CDK4/6 inhibitors to that of traditional neoadjuvant chemotherapy.
A total of 49 patients receiving neoadjuvant endocrine therapy plus CDK4/6 inhibitors and 210 receiving neoadjuvant chemotherapy were enrolled. Magnetic resonance imaging was performed to assess tumor responses every 2-3 cycles of treatment. Propensity score matching (PSM) was performed to balance baseline characteristics.
Both before and after PSM, the objective response rate (ORR) in the endocrine therapy group was comparable to that of the traditional chemotherapy group. After matching, the ORR was 64.6% (95% CI, 49.5-77.8) in the endocrine group and 56.3% (95% CI, 41.2-70.5) in the chemotherapy group (P = .532). A higher proportion of patients in the endocrine group achieved a pathological complete or near-complete response (Miller-Payne grades 4-5, 13.5% vs 10.4%) and post-treatment Ki67 < 5%, indicating a potential long-term benefit. Patients with ≥30% regression in maximal tumor diameter after 2 cycles of chemotherapy were considered chemotherapy sensitive. Among patients with tumors less sensitive to chemotherapy, sequential treatment with neoadjuvant endocrine therapy plus CDK4/6 inhibitors significantly improved ORR (61.8% vs 32.4%, P = .028) and was associated with greater Ki67 reduction and improved Miller-Payne grades.
Neoadjuvant endocrine therapy is a promising alternative for HR-positive breast cancer, especially for patients with poor responses to chemotherapy.
激素受体（HR）阳性乳腺癌的新辅助治疗仍然有限，尤其是对于对新辅助化疗不敏感的肿瘤。本研究旨在比较新辅助内分泌治疗联合CDK4/6抑制剂与传统新辅助化疗的疗效。
共纳入49例接受新辅助内分泌治疗加CDK4/6抑制剂的患者和210例接受新辅助化疗的患者。在每2 - 3个治疗周期进行磁共振成像以评估肿瘤反应。采用倾向评分匹配（PSM）来平衡基线特征。
在PSM前后，内分泌治疗组的客观缓解率（ORR）与传统化疗组相当。匹配后，内分泌组的ORR为64.6%（95%CI，49.5 - 77.8），化疗组为56.3%（95%CI，41.2 - 70.5）（P = 0.532）。内分泌组中达到病理完全或接近完全缓解（米勒 - 佩恩分级4 - 5级）以及治疗后Ki67＜5%的患者比例更高，表明可能有长期获益。在2个周期化疗后最大肿瘤直径缩小≥30%的患者被认为对化疗敏感。在对化疗不太敏感的肿瘤患者中，新辅助内分泌治疗联合CDK4/6抑制剂序贯治疗显著提高了ORR（61.8%对32.4%，P = 0.028），并与更大程度的Ki67降低和改善的米勒 - 佩恩分级相关。
新辅助内分泌治疗是HR阳性乳腺癌的一种有前景的替代治疗方法，尤其是对于化疗反应不佳的患者。
