Department of Cellular Pathology, Queen Elizabeth Hospital Birmingham and Cancer and Genomic Sciences, University of Birmingham, Birmingham, UK.
Department of Pathology, Cambridge Breast Unit, and NIHR Cambridge Biomedical Research Centre, Cambridge University Hospitals NHS Trust, Cambridge, UK.
Pathobiology. 2022;89(5):297-308. doi: 10.1159/000521880. Epub 2022 May 30.
Neoadjuvant chemotherapy (NACT) is now established in routine management of early breast cancer. Alterations in oestrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) following NACT are reported, with wide variation in results across series. In larger series, changes in ER status are identified in 5-23%, whilst changes in PR status are more frequent (14.5-67%). HER2 status changes less frequently with loss being more common than gain, and higher rates of change with immunohistochemistry are observed compared to in situ hybridization and following HER2-targeted therapy compared with chemotherapy alone. Triple negative is the most stable molecular subtype with combined ER, and HER2-positive cancers show the highest rate of change. Neoadjuvant endocrine therapy is used less commonly than NACT, and whilst loss of ER is rare, changes in PR status can occur in up to 40% of cases. There is relatively little published data on the impact of change in receptor status on survival outcomes. In patients whose tumours become ER or HER2 positive post-NACT, endocrine or anti-HER2 therapy can be initiated, although evidence from clinical trials is lacking. Most guidelines do not currently recommend routine retesting; however it should be considered in some circumstances.
新辅助化疗（NACT）现在已成为早期乳腺癌常规治疗的一部分。据报道，NACT 后雌激素受体（ER）、孕激素受体（PR）和人表皮生长因子受体 2（HER2）发生改变，不同研究结果差异较大。在较大的系列研究中，ER 状态改变的发生率为 5-23%，而 PR 状态改变更为常见（14.5-67%）。HER2 状态改变的频率较低，丢失比获得更为常见，与原位杂交相比，免疫组化检测到的变化率更高，与单独化疗相比，HER2 靶向治疗后变化率更高。三阴性是最稳定的分子亚型，ER 和 HER2 阳性癌症的改变率最高。与 NACT 相比，新辅助内分泌治疗的应用较少，虽然 ER 丢失罕见，但 PR 状态的改变可发生在多达 40%的病例中。关于受体状态改变对生存结果的影响，相关研究数据相对较少。在 NACT 后肿瘤转为 ER 或 HER2 阳性的患者中，可以启动内分泌或抗 HER2 治疗，尽管缺乏临床试验证据。大多数指南目前不建议常规进行重新检测；然而，在某些情况下，应考虑进行重新检测。
