原发性纵隔B细胞淋巴瘤（PMBCL）是一种独特的临床病理学实体。目前，缺乏随机前瞻性数据来确定最佳一线化疗免疫疗法（CIT）和紧急用途的纵隔辐射（RT）。为了评估不同的CIT方案是否与不同的生存结局相关，我们进行了一项系统回顾与荟萃分析，比较了剂量密集(DI-CIT)和标准CIT对PMBCL一线治疗的疗效。标准方案(S-CIT)定义为R-CHOP-21/CHOP-21，带或不带RT。增加剂量、频率和/或系统药物数量的方案定义为DI-CIT。我们回顾了4068例新诊断的PMBCL患者的数据（2517例DI-CIT；1551例S-CIT）。DI-CIT患者的总体生存率为88％（95％CI：85-90），而S-CIT队列为80％（95％CI：74-85）。荟萃回归分析显示DI-CIT组患者的总体生存率增加了8％（p < 0.01）。当分析仅含利妥昔单抗方案时，该生存益处仍然存在；利妥昔单抗-DI-CIT臂的总生存率为91％（95％CI：89-93），而R-CHOP-21臂为86％（95％CI：82-89）（p = 0.03）。值得注意的是，55％（95％CI：43-65）的S-CIT组接受了RT，而DI-CIT患者仅有22％（95％CI：15-31）接受了RT（荟萃回归分析p < 0.01）。据我们所知，这是最大的一项荟萃分析，针对PMBCL的一线治疗报告了疗效结果。DI-CIT具有生存益处，且放射治疗的暴露显著减少，可减轻与放射治疗相关的长期毒性。在等待随机前瞻性试验结果的同时，我们的研究支持采用剂量密集化疗免疫疗法治疗PMBCL。

Primary mediastinal B-cell lymphoma (PMBCL) is a distinct clinicopathologic entity. Currently, there is a paucity of randomized prospective data to inform on optimal frontline chemoimmunotherapy (CIT) and use of consolidative mediastinal radiation (RT). To assess if distinct CIT approaches are associated with disparate survival outcomes, we performed a systematic review and meta-analysis comparing dose-intensive (DI-CIT) versus standard CIT for the frontline treatment of PMBCL. Standard approach (S-CIT) was defined as R-CHOP-21/CHOP-21, with or without RT. DI-CIT were defined as regimens with increased frequency, dose, and/or number of systemic agents. We reviewed data on 4068 patients (2517 DI-CIT; 1551 S-CIT) with a new diagnosis of PMBCL. Overall survival for DI-CIT patients was 88% (95% CI: 85-90) compared to 80% for the S-CIT cohort (95% CI: 74-85). Meta-regression revealed an 8% overall survival benefit for the DI-CIT group (p < 0.01). Survival benefit was maintained when analyzing rituximab only regimens; OS was 91% (95% CI: 89-93) for the rituximab-DI-CIT arm, compared to 86% (95% CI: 82-89) for the R-CHOP-21 arm (p = 0.03). Importantly, 55% (95% CI: 43-65) of the S-CIT group received RT compared to 22% (95% CI: 15-31) of DI-CIT patients (meta-regression p < 0.01). To our knowledge, this is the largest meta-analysis reporting efficacy outcomes for the frontline treatment of PMBCL. DI-CIT demonstrates a survival benefit, with significantly less radiation exposure, curtailing long-term toxicities associated with radiotherapy. As we await results of randomized prospective trials, our study supports the use of dose-intensive chemoimmunotherapy for the treatment of PMBCL.