A systematic literature research was carried out to identify studies comparing survival outcomes of patients affected by HER2-low versus HER2-zero breast cancer. Using random-effects models, pooled hazard ratios (HRs) and odds ratios (ORs) with 95% confidence intervals (CIs) were calculated for progression-free survival (PFS) and overall survival (OS) in the metastatic setting as well as disease-free survival (DFS), OS and pathological complete response (pCR) in the early setting. Subgroup analyses by hormone receptor (HoR) status were carried out. The study protocol is registered on PROSPERO (n.CRD42023390777).
Among 1916 identified records, 42 studies including 1 797 175 patients were eligible. In the early setting, HER2-low status was associated with significant improved DFS (HR 0.86, 95% CI 0.79-0.92, P < 0.001) and OS (HR 0.90, 95% CI 0.85-0.95, P < 0.001) when compared to HER2-zero status. Improved OS was observed for both HoR-positive and HoR-negative HER2-low populations, while DFS improvement was observed only in the HoR-positive subgroup. HER2-low status was significantly associated with a lower rate of pCR as compared to HER2-zero status both in the overall population (OR 0.74, 95% CI 0.62-0.88, P = 0.001) and in the HoR-positive subgroup (OR 0.77, 95% CI 0.65-0.90, P = 0.001). In the metastatic setting, patients with HER2-low breast cancers showed better OS when compared with those with HER2-zero tumours in the overall population (HR 0.94, 95% CI 0.89-0.98, P = 0.008), regardless of HoR status. No significant PFS differences were found.
Compared with HER2-zero status, HER2-low status appears to be associated with a slightly increased OS both in the advanced and early settings, regardless of HoR expression. In the early setting, HER2-low tumours seem to be associated to lower pCR rates, especially if HoR-positive.
方法:进行了一项系统性文献研究,以确定比较低HER2与零HER2乳腺癌患者生存结局的研究。使用随机效应模型,计算无进展生存期(PFS)和总生存期(OS)以及无疾病生存期(DFS)的合并风险比(HR)和比值比(OR)以及95%置信区间(CI),OS和早期病理完全缓解(pCR)。通过激素受体(HoR)状态进行亚组分析。研究方案已在PROSPERO上注册(n。CRD42023390777)。
结果:在1916个确定的记录中,42项研究,包括1797175例患者。在早期设置,与HER2零状态相比,HER2低状态与DFS(HR0.86,95%CI0.79-0.92,P<0.001)和OS(HR0.90,95%CI0.85-0.95,P<0.001)显着改善相关。对于HoR阳性和HoR阴性的HER2低人群,观察到OS改善。而仅在HoR阳性亚组观察到DFS改善。在总体人群(OR0.74,95%CI0.62-0.88,P=0.001)和HoR阳性亚组(OR0.77,95%CI0.65-0.90,P=0.001)中,HER2低状态与较低的pCR率显著相关。在转移性环境中,在总体人群中,低HER2乳腺癌患者的OS优于低HER2乳腺癌患者(HR0.94,95%CI0.89-0.98,P=0.008),无论HoR状态如何。没有发现显著的PFS差异。
结论:与HER2零状态相比,在高级和早期设置中,HER2低状态似乎与操作系统略有增加有关,不考虑HoR表达式。在早期设置,低HER2肿瘤似乎与较低的pCR率有关,特别是如果HoR阳性。