'Sandro Pitigliani' Medical Oncology Department, Hospital of Prato, Istituto Toscano Tumori, Prato, Italy.
Cancer Treat Rev. 2013 Dec;39(8):947-57. doi: 10.1016/j.ctrv.2013.05.003. Epub 2013 Jun 10.
In the setting of breast cancer relapse, treatment decisions are typically made by utilizing HER2, estrogen, and progesterone receptor expression status of the primary breast cancer. Recently, concern regarding receptor discordance has led to recommendations for rebiopsy for all cases of metastatic disease. However, whether this is an appropriate recommendation is uncertain, particularly as the clinical implications for HER2 discordance are unknown.
We performed a literature review to identify studies assessing HER2 discordance between primary and metastatic breast cancer. These studies were then reviewed for data relating to (1) impact of clinical factors on discordance rates, (2) prognostic impact of discordance, or (3) clinical outcomes from treatment alteration due to receptor discordance. Results were analyzed qualitatively.
From 60 HER2 discordance studies identified, 24 contained information of interest for this review. No clear factor promoting HER2 discordance was identified. Loss of HER2 seemed to result in worse post-relapse survival and overall survival, although these data were often confounded by lack of treatment in the setting of receptor loss. Conversely, HER2 discordance was not associated with shorter DFS. Individual patients with receptor gain appear to have benefited from addition of targeted treatment, although data are limited to case reports.
Evidence of HER2 discordance leading to alterations in patient outcomes is limited, highlighting the need for further research in this area. Furthermore, lack of alteration in patient outcomes suggests that a more pragmatic approach to the decision to rebiopsy may be appropriate.
在乳腺癌复发的情况下，通常通过利用原发性乳腺癌的 HER2、雌激素和孕激素受体表达状态来做出治疗决策。最近，由于对受体不一致性的担忧，建议对所有转移性疾病的病例进行再次活检。然而，这种建议是否合理尚不确定，特别是因为 HER2 不一致性的临床意义尚不清楚。
我们进行了文献综述，以确定评估原发性和转移性乳腺癌之间 HER2 不一致性的研究。然后，对这些研究进行了回顾，以获取与以下内容相关的数据：（1）临床因素对不一致性发生率的影响，（2）不一致性的预后影响，或（3）由于受体不一致性而改变治疗的临床结果。结果进行了定性分析。
从 60 项 HER2 不一致性研究中确定了 24 项包含了本综述感兴趣的信息。没有明确的因素可以促进 HER2 不一致性。HER2 丢失似乎导致复发后生存和总生存更差，尽管这些数据通常因受体丢失时缺乏治疗而受到混淆。相反，HER2 不一致性与无病生存期缩短无关。个别受体增益的患者似乎从添加靶向治疗中受益，尽管数据仅限于病例报告。
HER2 不一致性导致患者结局改变的证据有限，突出了该领域进一步研究的必要性。此外，患者结局没有改变表明，对再次活检的决定采取更务实的方法可能是合适的。
