Aims and Objectives

High dose methotrexate (HDMTx) based chemotherapy forms the backbone of therapy for patients with Primary Central Nervous system Lymphoma (PCNSL). However, delivering HDMTx in resource constrained settings, especially without therapeutic drug monitoring, is difficult. We share our experience of treatment of patients with PCNSL at our center over a 10-year period with local adaptations made to deliver HDMTx.

Materials and Methods

We retrospectively analysed the case records of patients diagnosed with a PCNSL over the course of 10 years from 2010 to 2020.

Results

Fifty-five patients received therapy for newly diagnosed PCNSL. Thirty-six patients received Modified De-Angelis protocol ± Rituximab with curative intent. Fourteen of these patients were unable to complete the protocol with the most common cause being development of methotrexate toxicity. Patients unable to complete the designated 5 cycles of HDMTx had a poorer PS and higher probability of having a high IELSG score at baseline. Nineteen patients were given non HDMTx based therapy either due to advanced age or poor performance status. Twenty-nine patients (52.7%) were able to achieve a complete response. The most common cause of mortality was relapse/progressive disease. The Median EFS and OS of the cohort was 29 months and 40 months respectively.

Conclusion

All attempts should be made to have therapeutic drug level monitoring for administration of HDMTX based therapy for the patients with PCNSL, more so in patients who have poor performance status and a high IELSG score. If it is imperative to give HDMTx without access to TDM facility then a possible risk of higher toxicity should be explained to all patients, beforehand

中文翻译：

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成功使用高剂量甲氨蝶呤治疗原发性 CNS 淋巴瘤患者，但无法进行血清甲氨蝶呤水平监测：挑战和结果

目的和目标

基于高剂量甲氨蝶呤 (HDMTx) 的化疗构成了原发性中枢神经系统淋巴瘤 (PCNSL) 患者治疗的支柱。然而，在资源受限的环境中提供 HDMTx 很困难，尤其是在没有治疗药物监测的情况下。我们分享了 10 年来在我们中心治疗 PCNSL 患者的经验，并进行了局部调整以提供 HDMTx。

材料和方法

我们回顾性分析了 2010 年至 2020 年 10 年间诊断为 PCNSL 的患者的病例记录。

结果

55 名患者接受了新诊断 PCNSL 的治疗。36 名患者接受了改良的 De-Angelis 方案±利妥昔单抗治疗。这些患者中有 14 名无法完成方案，最常见的原因是出现甲氨蝶呤毒性。无法完成指定的 5 个 HDMTx 周期的患者的 PS 较差，基线时 IELSG 评分较高的可能性较高。19 名患者由于年事已高或身体状况不佳而接受了非基于 HDMTx 的治疗。29 名患者 (52.7%) 能够获得完全缓解。最常见的死亡原因是复发/疾病进展。该队列的中位 EFS 和 OS 分别为 29 个月和 40 个月。

结论

应尽一切努力对 PCNSL 患者进行基于 HDMTX 的治疗的治疗药物水平监测，尤其是对体能状态较差和 IELSG 评分较高的患者。如果必须在无法进入 TDM 设施的情况下给予 HDMTx，则应事先向所有患者解释可能存在更高毒性的风险