Chemoradiotherapy with temozolomide after high-dose methotrexate for primary CNS lymphoma: a multicenter phase I study of a response-adapted strategy

Efficacy and toxicity with radiation field designs and concurrent temozolomide for CNS lymphoma

BACKGROUND

There is no consensus on the treatment of central nervous system (CNS) lymphoma refractory to first-line methotrexate-based chemotherapy. Whole brain radiotherapy (WBRT) is sometimes used but may result in unacceptable neurocognitive dysfunction. We examined the efficacy and toxicities of WBRT with or without concurrent temozolomide in CNS lymphoma treatment.

METHODS

This single-institution IRB-approved retrospective study included adults with CNS lymphoma who received WBRT, either consolidative low-dose WBRT alone or low-dose WBRT with a focal boost to residual disease and were previously treated with high-dose methotrexate. The relationships between the WBRT regimen, concurrent temozolomide, and clinical outcomes and toxicities were assessed using proportional hazards and logistic regression models.

RESULTS

A total of 45 patients with a median age of 64 years (range 24-74) treated from 2004 to 2019 were included. In total, 20 patients received concurrent temozolomide. In the WBRT + Boost cohort (n = 32), concurrent temozolomide resulted in better 2-year overall survival (OS) and progression free survival (PFS) (73% OS and 66% PFS) compared to patients treated without concurrent temozolomide (44% OS and 24% PFS). On multivariate analysis, concurrent temozolomide was associated with significantly better PFS (HR 0.28, P = .02). There were no significant differences between the two radiation groups or between those treated with or without concurrent temozolomide, with respect to significant acute hematologic, non-hematologic, and long-term neurocognitive toxicities (P > .05).

CONCLUSIONS

In this study, concurrent temozolomide with radiotherapy in CNS lymphoma was associated with better PFS and was well tolerated. Low-dose WBRT with a boost is a safe and reasonable treatment approach for focal refractory disease. Prospective research that includes rigorous neurocognitive assessments is now warranted.

Diagnostic accuracy of arterial spin labeling in differentiating between primary central nervous system lymphoma and high-grade glioma: a systematic review and meta-analysis

BACKGROUND

Existing studies have confirmed the accuracy of arterial spin labeling (ASL) in differentiating between primary central nervous system lymphoma (PCNSL) and high-grade glioma (HGG). We aimed to consolidate the existing evidence with a meta-analysis.

METHODS

Six literature databases were searched for relevant papers. After assessing the quality of studies, bivariate regression was performed, and the pooled sensitivity (SEN), specificity (SPE), positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic score, diagnostic odds ratio (DOR), and the area under the curve (AUC) of the summary receiver operating characteristic (SROC) curve were calculated, along with the corresponding 95% confidence intervals (CIs). Deeks' test was used to determine risk of publication bias.

RESULTS

Ten high-quality studies, comprising 151 patients with PCNSL and 455 with HGG, were included. The pooled SEN was 0.79 (95% CI: 0.72-0.85), pooled SPE was 0.90 (95% CI: 0.84-0.94), pooled PLR was 8.07 (95% CI: 5.01-13.02), pooled NLR was 0.23 (95% CI: 0.17-0.32), pooled diagnostic score was 3.56 (95% CI: 2.94-4.18), and pooled DOR was 35.10 (95% CI: 18.83-65.45). The AUC of SROC was 0.86 (95% CI: 0.83-0.89). No publication bias was found.

CONCLUSIONS

ASL demonstrated high diagnostic accuracy in differentiating between PCNSL and HGG.

PrACTiC: A Predictive Algorithm for Chemoradiotherapy-Induced Cytopenia in Glioblastoma Patients

Background

Chemotherapy-induced cytopenia is the most frequent side effect of chemoradiotherapy in glioblastoma patients which may lead to reduced delivery of treatment. This study aims to develop a predictive model that is able to forecast the cytopenia induced by temozolomide (TMZ) during concomitant chemoradiotherapy.

Methods

Medical records of 128 patients with newly diagnosed glioblastoma were evaluated to extract the baseline complete blood test before and during the six weeks of chemoradiotherapy to create a dataset for the development of ML models. Using the constructed dataset, different ML algorithms were trained and tested.

Results

Our proposed algorithm achieved accuracies of 85.6%, 88.7%, and 89.3% in predicting thrombocytopenia, lymphopenia, and neutropenia, respectively.

Conclusions

The algorithm designed and developed in this study, called PrACTiC, showed promising results in the accurate prediction of thrombocytopenia, neutropenia, and lymphopenia induced by TMZ in glioblastoma patients. PrACTiC can provide valuable insight for physicians and help them to make the necessary treatment modifications and prevent the toxicities.

Advances in treatment of elderly primary central nervous system lymphoma

The management of older individuals (≥60 years) with primary central nervous system lymphoma remains a clinical challenge. Identification of optimal therapy and delivering adequate dose intensity are two of the major issues in treating elderly patients. Premorbid performance status and comorbidities influence individualised treatment approaches and geriatric assessment tools are increasingly utilised. Optimal induction treatment remains high-dose methotrexate-based immunochemotherapy, delivery is feasible in the majority of patients and the goal of treatment remains achieving complete remission. Consolidation strategies are also relevant in the elderly, aiming to maximise duration of response and quality of life (QoL). Potential options include high-dose therapy with haematopoietic stem cell consolidation, non-myeloablative chemotherapy and whole-brain radiotherapy. Efficacy of novel agents, such as Bruton tyrosine kinase inhibitors and lenalidomide, have been reported; these represent an alternative for elderly patients unfit for chemotherapy. Prognosis remains poor, improvement of outcomes in this age group is urgently needed.

Recent Progress on Primary Central Nervous System Lymphoma-From Bench to Bedside

Primary central nervous system lymphoma (PCNSL) is a rare subtype of extra-nodal lymphoma. The high relapse rate of PCNSL remains a major challenge to the hematologists, even though patients exhibit high sensitivity to the methotrexate-based chemotherapeutic regimens. Recently, the advent of Bruton's tyrosine kinase inhibitor (BTKi) and CAR T treatment has made more treatment options available to a proportion of patients. However, whether BTKi monotherapy should be given alone or in combination with conventional chemotherapy is still a clinical question. The status of CAR T therapy for PCNSLs also needs to be elucidated. In this review, we summarized the latest progress on the epidemiology, pathology, clinical manifestation, diagnosis, and treatment options for PCNSLs.