【背景】免疫治疗时代下局部巩固放疗（cRT）在寡转移非小细胞肺癌（oligo-NSCLC）中的价值尚存争议，且不同PD-L1表达水平和基线是否存在脑转移对cRT疗效的影响需要深入探索。
【方法】本研究基于多中心回顾性队列，纳入2017年1月至2023年1月接受一线化疗联合免疫治疗的240例寡转移NSCLC患者，所有患者均行肿瘤组织PD-L1表达水平检测。通过逆概率加权（IPTW）校正混杂因素，分析不同PD-L1表达水平及基线是否存在脑转移cRT对生存影响的差异。研究终点包括总生存期（OS）、无进展生存期（PFS）和安全性等。
【结果】本研究共纳入240例患者，其中化免治疗组（ICI）156例，ICI联合巩固放疗组（ICI+cRT）84例。PD-L1肿瘤比例评分（TPS）分布为：30.4%（TPS=0）、35.0%（TPS 1-49%）及34.6%（TPS≥50%）。经过IPTW矫正后，ICI组与ICI+cRT组之间基线特征无统计学差异（P>0.05）。全队列中，ICI+cRT组与ICI组的PFS（HR=0.73,P=0.083）和OS（HR=0.67,P=0.077）均无显著差异。PD-L1亚组分析显示，PD-L1阴性/低表达（TPS 0-49%）患者中，ICI+cRT组PFS（HR=0.59,P=0.009）和OS（HR=0.59,P=0.016）显著优于ICI组，联合治疗组中位PFS从10.6个月延长至16.8个月，2年OS从48%提升至74%；而PD-L1高表达（TPS≥50%）患者无额外获益（PFS: HR=1.06; P= 0.862; OS:HR=0.88,P=0.976）。在基线脑转移患者（n=98）中，ICI+cRT组较ICI组OS显著改善（中位OS未达到vs.22.3个月，HR=0.47,P=0.036），PFS虽未达显著性差但观察到改善趋势（中位PFS 21.8个月VS 11.5个月，HR=0.68，P=0.21）。安全性方面未观察到两组不良事件发生率有统计学差异。
【结论】PD-L1低表达（TPS 0-49%）及脑转移寡转移NSCLC患者可能从cRT联合IO中显著获益，提示基于生物标志物的分层治疗策略具有重要临床意义。

Background: The role of consolidative radiotherapy (cRT) combined with immunotherapy (ICI) in oligometastatic non-small cell lung cancer (oligo-NSCLC) remains controversial, particularly regarding PD-L1 expression and central nervous system (CNS) involvement.
Methods: This multicenter retrospective study included 240 oligo-NSCLC patients treated with first-line platinum-based chemotherapy plus ICI between 2017 and 2023. Patients were stratified into ICI+cRT and ICI groups. Inverse probability weighting (IPTW) was used to adjust baseline imbalances. Subgroup analyses focused on PD-L1 expression and brain metastasis. Primary endpoints were overall survival (OS) and progression-free survival (PFS).
Results: A total of 240 patients were enrolled in this study, including 156 in the ICI group and 84 in the ICI plus consolidative radiotherapy (ICI+cRT) group. No statistically significant differences in baseline characteristics were observed between the ICI and ICI+cRT groups (P > 0.05). In the overall cohort, no significant differences were observed after IPTW in PFS (HR = 0.73, P = 0.083) or OS (HR = 0.67, P = 0.077) between ICI+cRT and ICI groups. However, PD-L1-low (TPS 0-49%) patients receiving ICI+cRT showed significantly improved PFS (HR = 0.59, P = 0.009) and OS (HR = 0.59, P = 0.016), while PD-L1-high (TPS ≥ 50%) patients derived no additional benefit. Among 98 patients with baseline brain metastasis, ICI+cRT demonstrated superior OS (median not reached vs. 22.3 months, HR = 0.47, P = 0.036), particularly in those with ≤ 3 metastatic lesions (OS HR = 0.34, P = 0.046). Safety profiles were comparable between groups.
Conclusion: PD-L1-negative/low oligo-NSCLC patients and those with CNS involvement may achieve significant survival benefits from cRT combined with ICI, highlighting the importance of biomarker-driven therapeutic stratification.