Department of Pathology, Fudan University Shanghai Cancer Center, China; Department of Pathology, Tongji Hospital, School of Medicine, Tongji University, Shanghai, China.
Department of Pathology, Fudan University Shanghai Cancer Center, China; Department of Oncology, Shanghai Medical College, Fudan University, China; Institute of Pathology, Fudan University, Shanghai, China.
Clin Breast Cancer. 2023 Jun;23(4):436-446. doi: 10.1016/j.clbc.2023.03.002. Epub 2023 Mar 8.
Few studies have focused on converting ER-low-positive and HER2-low status following neoadjuvant therapy (NAT). We aimed to assess the evolution in ER and HER2 status after NAT in breast cancer patients.
Our study included 481 patients with residual invasive breast cancer after NAT. ER and HER2 status were assessed in the primary tumor and residual disease, and associations between ER and HER2 conversion and clinicopathological factors were explored.
In primary tumors, 305 (63.4%) cases were ER-positive (including 36 cases of ER-low-positive), 176 (36.6%) were ER-negative. In residual disease, ER status changed in 76 (15.8%) cases, of which 69 cases switched from positive to negative. ER-low-positive tumors (31/36) were the most likely to change. In primary tumors, 140 (29.1%) tumors were HER2-positive, and 341 (70.9%) were HER2-negative (including 209 cases of HER2-low and 132 cases of HER2-zero). In residual disease, 25 (5.2%) cases had HER2 conversion between positive and negative. Considering HER2-low status, 113 (23.5%) cases had HER2 conversion, mostly driven by cases switching either to or from HER2-low. ER conversion had a positive correlation with pretreatment ER status (r = 0.25; P = .00). There was a positive correlation between HER2 conversion and HER2-targeted therapy (r = 0.18; P = .00).
Conversion of ER and HER2 status was observed in some breast cancer patients after NAT. Both ER-low-positive and HER2-low tumors showed high instability from the primary tumor to residual disease. ER and HER2 status should be retested in residual disease for further treatment decisions, especially in ER-low-positive and HER2-low breast cancer.
鲜有研究聚焦于新辅助治疗（NAT）后 ER-低阳性和 HER2-低状态的转化。我们旨在评估乳腺癌患者 NAT 后 ER 和 HER2 状态的演变。
本研究纳入了 481 例 NAT 后仍有浸润性乳腺癌残留的患者。评估了原发肿瘤和残留病灶中的 ER 和 HER2 状态，并探讨了 ER 和 HER2 转化与临床病理因素之间的关系。
在原发肿瘤中，305 例（63.4%）为 ER 阳性（包括 36 例 ER-低阳性），176 例（36.6%）为 ER 阴性。在残留病灶中，76 例（15.8%）的 ER 状态发生改变，其中 69 例由阳性转为阴性。ER-低阳性肿瘤（31/36）最有可能发生变化。在原发肿瘤中，140 例（29.1%）为 HER2 阳性，341 例（70.9%）为 HER2 阴性（包括 209 例 HER2-低和 132 例 HER2-零）。在残留病灶中，25 例（5.2%）的 HER2 状态由阳性转为阴性。考虑到 HER2-低状态，113 例（23.5%）的病例发生了 HER2 转化，主要是 HER2-低和 HER2-零之间的转换。ER 转化与预处理 ER 状态呈正相关（r=0.25；P=.00）。HER2 转化与 HER2 靶向治疗呈正相关（r=0.18；P=.00）。
一些乳腺癌患者在 NAT 后出现了 ER 和 HER2 状态的转化。ER-低阳性和 HER2-低肿瘤在原发肿瘤到残留病灶的过程中均表现出较高的不稳定性。对于进一步的治疗决策，尤其是在 ER-低阳性和 HER2-低的乳腺癌中，应在残留病灶中重新检测 ER 和 HER2 状态。
