最近的研究调查了免疫检查点抑制剂（ICIs）与（新）辅助化疗联合治疗早期乳腺癌的情况。然而，关于整合这一策略的最佳方法一直存在争论。 评估新辅助 ICI 与跨分子表型的病理完全缓解 (pCR) 的关联，量化 ICI 超出 pCR 状态的生存获益，并估计发病率于 2023 年 12 月 10 日检索了 PubMed 数据库，以确定所有潜在的合格研究。评估早期乳腺癌（新）辅助 ICI 联合化疗的随机临床试验 (RCT)。从合格的 RCT 中提取数据由2位审稿人。进行了提取的个体患者数据荟萃分析和试验水平随机效应荟萃分析。结果包括 pCR、有或没有 pCR 患者的无事件生存期 (EFS) 以及不良事件。使用分层 Cox 比例风险回归模型估计风险比。涉及 5114 名患者的 9 项 RCT 符合纳入标准（2097 名三阴性乳腺癌 [TNBC]、1924 名激素受体阳性 [HR]/ERBB2 阴性 [ERBB2-] 和1115 ERBB2 肿瘤）。在 TNBC 中，无论程序性细胞死亡配体 1 (PD-L1) 状态如何，添加 ICI 都与 pCR 率改善相关（绝对改善，>10%）。在HR/ERBB2-肿瘤中，ICIs的施用仅在PD-L1阳性(PD-L1)群体中与pCR改善相关(绝对改善，12.2%)，而在ERBB2肿瘤中没有观察到任何益处。在达到 pCR 的 TNBC 患者中，添加 ICI 与 EFS 改善相关（风险比，0.65；95% CI，0.42-1.00），使用 ICI 的 5 年 EFS 为 92.0%，而未使用 ICI 的 5 年 EFS 为 88.0% 。在有残留病灶的患者中，ICIs 还显示出更好的 EFS（风险比，0.77；95% CI，0.61-0.98），使用 ICI 的 5 年 EFS 为 63.3%，不使用 ICI 的 5 年 EFS 为 56.1%。对于 pCR 或残留疾病的患者（所有风险比 >1），辅助 ICI 并未显示数值改善。在新辅助治疗期间，ICI 引起的 3 级或以上免疫相关不良事件的发生率为 10.3%。这些研究结果表明，新辅助 ICI 治疗可改善早期 TNBC 和 PD-L1 HR /ERBB2- 肿瘤的疗效结果，且可接受的治疗效果良好。安全概况；然而，辅助 ICI 没有观察到任何益处。考虑到与 ICI 相关的财务和毒性成本，未来的研究应优先确定最有可能从新辅助化疗中添加 ICI 中受益的患者。

Recent studies have investigated the combination of immune checkpoint inhibitors (ICIs) with (neo)adjuvant chemotherapy in early-stage breast cancer. However, there is an ongoing debate about the optimal approach for integrating this strategy.To evaluate the association of neoadjuvant ICIs with pathologic complete response (pCR) across molecular phenotypes, to quantify the survival benefits of ICIs beyond pCR status, and to estimate the incidence of specific adverse events.The PubMed database was searched on December 10, 2023, to identify all potential eligible studies.Randomized clinical trials (RCTs) that assessed (neo)adjuvant ICI plus chemotherapy in early breast cancer.Data from the eligible RCTs were extracted by 2 reviewers. An extracted individual patient data meta-analysis and a trial-level random-effect meta-analysis were performed.Outcomes were pCR, event-free survival (EFS) in patients with and without pCR, and adverse events. Hazard ratios were estimated using stratified Cox proportional hazards regression models.Nine RCTs involving 5114 patients met the inclusion criteria (2097 triple-negative breast cancer [TNBC], 1924 hormone receptor-positive [HR+]/ERBB2-negative [ERBB2-], and 1115 ERBB2+ tumors). In TNBC, the addition of ICIs was associated with an improved pCR rate regardless of programmed cell death ligand 1 (PD-L1) status (absolute improvement, >10%). In HR+/ ERBB2- tumors, the administration of ICIs was associated with improved pCR only in the PD-L1-positive (PD-L1+) population (absolute improvement, +12.2%), whereas no benefit was observed in ERBB2+ tumors. In patients with TNBC achieving a pCR, the addition of ICIs was associated with improved EFS (hazard ratio, 0.65; 95% CI, 0.42-1.00), resulting in a 5-year EFS of 92.0% with ICIs compared with 88.0% without them. In patients with residual disease, ICIs also showed better EFS (hazard ratio, 0.77; 95% CI, 0.61-0.98), resulting in a 5-year EFS of 63.3% with ICIs and 56.1% without them. Adjuvant ICI did not show numerical improvement in patients with either pCR or residual disease (all hazard ratios >1). During the neoadjuvant treatment, the incidence of grade 3 or greater immune-related adverse events with ICI was 10.3%.These findings suggest that neoadjuvant ICI therapy improves efficacy outcomes in early-stage TNBC and PD-L1+ HR+/ERBB2- tumors with an acceptable safety profile; however, no benefit was observed with adjuvant ICI. Given the financial and toxicity costs associated with ICIs, future research should prioritize identifying patients most likely to benefit from the addition of ICIs to neoadjuvant chemotherapy.