原句：Clinical data on primary central nervous system (CNS) lymphoma (PCNSL) patients is mostly generated from prospective studies, and many frail real-world patients are not included. Recently, the diagnosis and treatment of PCNSL patients was confounded by the COVID-19 pandemic. In particular, treatment with high-dose cytarabine was linked to increased risk of pneumonia and virus persistence. We report on outcome of the induction regimen R-MIV (rituximab, methotrexate, ifosfamide, and vincristine) involving intensive administration of high-dose methotrexate (3.5 g/m2 ) with ifosfamide, every 2 weeks and rituximab once per week for six doses. The median age and performance status (PS) for 64 patients was 58 years and 2 (PS 3; 22%) respectively. The overall response rate by magnetic resonance imaging/computed tomography (MRI/CT) was 73% (n = 46/63), with an additional 17.5% (n = 11/63) patients without measurable disease at baseline. Grade 3-4 haematological toxicity was low for R-MIV (neutropenia: 25% and thrombocytopenia: 1%). Three patients (4.7%) died from treatment-related toxicity. Co-existence of SARS-CoV-2 infection with cytomegalovirus reactivation and the varicella-zoster virus in two patients was fatal. Fifty patients (78%) were eligible for consolidation. Median progression-free and overall survival were not reached (median follow-up: 44 months). In conclusion, the R-MIV regimen is feasible in routine practice, effective and safe, even during the COVID-19 pandemic.© 2023 The Authors. British Journal of Haematology published by British Society for Haematology and John Wiley & Sons Ltd. 原译：临床数据大多数来自前瞻性研究，而许多脆弱的现实患者并未被纳入。最近，COVID-19大流行对PCNSL患者的诊断和治疗造成了混乱。特别是，高剂量的阿糖胞苷治疗被认为增加了肺炎和病毒持续性的风险。我们报告了使用高剂量甲氨蝶呤（3.5 g/m2），伊福司胺和长春新碱每2周一次，以及利妥昔单抗每周一次6次的诱导方案R-MIV的疗效。64名患者的中位年龄和表现状态（PS) 分别为58岁和2（PS3；22%）。利用磁共振成像/计算机断层扫描（MRI/CT）的总体反应率为73%（n=46/63），还有17.5%的患者（n=11/63）在基线时没有可测量的疾病。R-MIV的3-4级血液毒性很低（中性粒细胞减少症：25%和血小板减少症：1%）。三名患者（4.7%）因治疗相关毒性死亡。两名患者同时感染严重急性呼吸综合征冠状病毒2（SARS-CoV-2）、巨细胞病毒复活和水痘带状疱疹病毒会导致死亡。50名患者（78%）符合巩固治疗条件。中位进展生存期和总生存期均未达到（中位随访期：44个月）。总之，R-MIV方案在常规实践中使用可行、有效且安全，即使在COVID-19大流行期间也是如此。© 2023 The Authors. British Journal of Haematology published by British Society for Haematology and John Wiley & Sons Ltd.

Clinical data on primary central nervous system (CNS) lymphoma (PCNSL) patients is mostly generated from prospective studies, and many frail real-world patients are not included. Recently,the diagnosis and treatment of PCNSL patients was confounded by the COVID-19 pandemic. In particular, treatment with high-dose cytarabine was linked to increased risk of pneumonia and virus persistence. We report on outcome of the induction regimen R-MIV (rituximab, methotrexate, ifosfamide, and vincristine) involving intensive administration of high-dose methotrexate (3.5 g/m2 ) with ifosfamide, every 2 weeks and rituximab once per week for six doses. The median age and performance status (PS) for 64 patients was 58 years and 2 (PS 3; 22%) respectively. The overall response rate by magnetic resonance imaging/computed tomography (MRI/CT) was 73% (n = 46/63), with an additional 17.5% (n = 11/63) patients without measurable disease at baseline. Grade 3-4 haematological toxicity was low for R-MIV (neutropenia: 25% and thrombocytopenia: 1%). Three patients (4.7%) died from treatment-related toxicity. Co-existence of SARS-CoV-2 infection with cytomegalovirus reactivation and the varicella-zoster virus in two patients was fatal. Fifty patients (78%) were eligible for consolidation. Median progression-free and overall survival were not reached (median follow-up: 44 months). In conclusion, the R-MIV regimen is feasible in routine practice, effective and safe, even during the COVID-19 pandemic.© 2023 The Authors. British Journal of Haematology published by British Society for Haematology and John Wiley & Sons Ltd.