Introduction

We aimed to investigate the role of upfront whole-brain radiation therapy (RT), with a reduced dose of 23.4 Gy, following high-dose methotrexate (HD-MTX) in patients with primary central nervous system lymphoma (PCNSL).

Methods

We retrospectively reviewed 185 patients with PCNSL treated with HD-MTX between January 2013 and January 2020; 145 patients underwent no RT and 40 patients underwent upfront RT. Using propensity score matching (PSM) to adjust for clinical factors, 40 patients were selected from each treatment group. Event-free survival (EFS) and overall survival (OS) were compared between treatment groups.

Results

At baseline, patients in the upfront RT group were younger, had higher LDH levels, received less frequent rituximab and stem cell transplantation than those in the no-RT group. Patients in the upfront RT group also showed a lower response rate after initial HD-MTX than those in the no-RT group (73% vs. 88%, p = 0.038). The median follow-up was 25.1 (interquartile range 13.7–43.0) months. Comparable 2-year EFS and OS rates were observed between the upfront RT and no-RT groups (56.6% vs. 53.8%, p = 0.170; and 81.7% vs. 75.3%, p = 0.097, respectively). Upfront RT was related to improved EFS and OS in patients with stable disease or progressive disease after HD-MTX, but not in patients with complete or partial response after HD-MTX. Upfront RT was also an independent predictor of EFS and OS in the PSM cohort. The cumulative incidences of treatment-related neurotoxicity at 3 years were 20.2% and 21.2% in the upfront RT and no-RT groups, respectively (p = 0.630).

Conclusions

Upfront RT with a reduced dose of 23.4 Gy, showed favorable outcomes in patients with stable disease or progressive disease after initial HD-MTX. In addition, upfront RT appears to be an effective treatment for PCNSL when rituximab or stem cell transplantation is not feasible.

中文翻译：

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大剂量甲氨蝶呤治疗原发性中枢神经系统淋巴瘤后 23.4 Gy 前期全脑放疗的作用：全脑放疗与不放疗的比较分析

介绍

我们的目的是研究在原发性中枢神经系统淋巴瘤 (PCNSL) 患者中使用大剂量甲氨蝶呤 (HD-MTX) 后减少剂量 23.4 Gy 的前期全脑放射治疗 (RT) 的作用。

方法

我们回顾性分析了 2013 年 1 月至 2020 年 1 月期间接受 HD-MTX 治疗的 185 例 PCNSL 患者；145 名患者未接受放疗，40 名患者接受了前期放疗。使用倾向评分匹配 (PSM) 调整临床因素，从每个治疗组中选择 40 名患者。比较治疗组之间的无事件生存期（EFS）和总生存期（OS）。

结果

在基线时，前期放疗组的患者比非放疗组的患者更年轻，LDH 水平更高，接受利妥昔单抗和干细胞移植的频率更低。前期放疗组的患者在初始 HD-MTX 后的反应率也低于非放疗组（73% 对 88%，p = 0.038）。中位随访时间为 25.1（四分位距 13.7-43.0）个月。在前期放疗组和非放疗组之间观察到可比较的 2 年 EFS 和 OS 率（分别为 56.6% 对 53.8%，p = 0.170；和 81.7% 对 75.3%，p = 0.097）。前期放疗与 HD-MTX 后疾病稳定或疾病进展患者的 EFS 和 OS 改善有关，但与 HD-MTX 后完全或部分缓解的患者无关。前期 RT 也是 PSM 队列中 EFS 和 OS 的独立预测因子。

结论

减少 23.4 Gy 剂量的前期放疗在初始 HD-MTX 后疾病稳定或疾病进展的患者中显示出良好的结果。此外，当利妥昔单抗或干细胞移植不可行时，前期 RT 似乎是 PCNSL 的有效治疗方法。