High-dose methotrexate-based chemotherapy followed by consolidating radiotherapy in non-AIDS-related primary central nervous system lymphoma: European Organization for Research and Treatment of Cancer Lymphoma Group Phase II Trial 20962

Consolidation Regimen and Cerebral Atrophy in Patients With Primary Central Nervous System Lymphoma

PURPOSE

In primary central nervous system lymphoma (PCNSL), the extent to which post-methotrexate consolidation contributes to neurotoxicity is unclear. Concerns for neurotoxicity from standard dose whole-brain radiation therapy (WBRT) have led to declining use. Cerebral atrophy is an established surrogate for neurotoxicity; however, the relative extent to which modern consolidation (ie, reduced-dose [RD-]WBRT ≤24 Gy, autologous hematopoietic cell transplant) contributes to cerebral atrophy is unclear.

METHODS AND MATERIALS

Patients with PCNSL from 2000-2020 who achieved a complete response to consolidation following methotrexate-based induction were included. Inclusion criteria were preconsolidation magnetic resonance imaging (baseline) and ≥1 magnetic resonance imaging showing sustained remission at 1, 3, 5, or 10 years. An expert neuroradiologist longitudinally measured parenchymal volume loss via ventricular volumetric change. Linear mixed-effects models were performed to estimate absolute and annual volumetric change rates.

RESULTS

Of 139 patients (median follow-up, 4.5 years), most were Memorial Sloan Kettering Cancer Center (MSK) recursive partitioning analysis (RPA) class 2 (age ≤50 years, Karnofsky performance score (KPS) ≥70). Consolidation therapies included nonmyeloablative chemotherapy (n = 57; 41%), high-dose myeloablative chemotherapy with autologous hematopoietic cell transplant (n = 50; 36%), and RD-WBRT (n = 28; 20%). A higher MSK RPA class was associated with greater baseline ventricular volume (P < .001). Overall adjusted annual ventricular volume change rates were greater than those published in healthy controls (4.3% vs 1.8%) and generally increased by age/decade at diagnosis: 40 to 49-year-olds 1.8% (95% CI, -1.4% to 5.0%), 50 to 59-year-olds 3.1% (95% CI, 0.7%-5.5%), 60 to 69-year-olds 4.8% (95% CI, 2.4%-7.3%), 70 to 79-year-olds 7.2% (95% CI, 4.3%-10.2%), and 80 to 89-year-olds 4.2% (95% CI, -1.1% to 9.6%). There were no significant associations between consolidation strategy and ventricular volume change rates accounting for age, KPS, gender, baseline ventricular volume, or interaction between age and consolidation.

CONCLUSIONS

These findings demonstrate accelerated cerebral atrophy in PCNSL after consolidation compared with healthy adults. However, atrophy did not differ by consolidation strategy. These long-term results suggest acceptable neurotoxicity following RD-WBRT.

Impact of Systemic and Radiation Therapy on Survival of Primary Central Nervous System Lymphoma

Introduction: Treatment for primary central nervous system lymphoma (PCNSL) includes high-dose methotrexate (HD-MTX)-based systemic therapy. Multiple regimens exist with no clear standard of care. We evaluated the impact of different therapies on PCNSL outcomes at a single institution. Materials and Methods: A total of 95 consecutive patients with PCNSL from 2002 to 2021 were retrospectively reviewed. The overall survival (OS) and progression-free survival (PFS) were estimated by the Kaplan-Meier method. The log-rank test and univariate and multivariable Cox regression analysis were used to evaluate the relationship between clinicopathologic and treatment variables with outcomes. Results: Among the 62 patients treated with definitive systemic therapy, the median age was 58; 71% had a Karnofsky performance status > 70, 49% had a single lesion, 31% received HD-MTX alone, and 61% had HD-MTX + rituximab. The two-year OS and PFS were 64% (95% CI: 49.8-75.0%) and 49% (95% CI: 35.0-60.9%), respectively. On multivariable analysis, the completion of > six cycles of HD-MTX (HR 0.40; 95% CI: 0.21-0.76; p = 0.01) was associated with superior OS, while the use of rituximab was associated with inferior OS (HR 2.82; 95% CI: 1.37-5.83; p = 0.01). There were no significant associations between the OS and PFS with temozolomide, the extent of surgical resection, radiation, or the size or number of initial lesions (all p > 0.05). Discussion: Innovation is needed to improve the outcomes for patients with PCNSL.

High-dose methotrexate-based chemotherapy for induction remission of newly diagnosed primary CNS lymphoma: A systematic review and meta-analysis

BACKGROUND

This study aimed to comprehensively assess the optimal regimen for high-dose methotrexate (HD-MTX) in treating primary central nervous system lymphoma (PCNSL).

METHODS

We have searched 8 databases, including PubMed, EMBASE, Cochrane Library, WOS, Epistemonikos, CNKI, WAN-FANG Database, and CBM, and were selected for the clinical trials about PCNSL. A total of 37 studies were included in our analysis, consisting of 6 randomized controlled trials and 31 single-arm clinical studies.

RESULTS

After analyzing the data from 37 clinical studies, we found that the pooled overall response rate (ORR) for low-dose (<3 g/m2), medium-dose (3-5 g/m2), and high-dose (>5 g/m2) methotrexate (MTX) were 0.78, 0.80, and 0.80, respectively. The pooled 2-year overall survival (OS) for low-dose, medium-dose, and high-dose MTX were 52%, 60%, and 71%, respectively. The ORR, complete response (CR), and 2-year OS of patients who received <5 cycles of MTX were 79%, 41%, and 59%, respectively, whereas those for PCNSL patients who received >5 cycles of MTX were 81%, 54%, and 64%, respectively. The pooled ORR for MTX, dual therapy, triplet therapy, tetrad therapy, and multiple therapy were 71%, 70%, 81%, 85%, and 80%, respectively. The pooled 2-year OS for different numbers of medication combinations were 59%, 52%, 66%, 63%, and 60%, respectively. The addition of cytarabine to MTX-based chemotherapy resulted in higher CR, although no statistically significant difference was observed in OS. Adding rituximab to the treatment regimen improved patients' progression-free survival without affecting treatment response or OS.

CONCLUSION

Based on the findings of this study, the treatment strategies of MTX are associated with the prognosis and efficacy response of PCNSL patients. The results suggested that the current recommended HD-MTX dosage of 3.5 g/m2 is sufficient for PCNSL to have a favorable treatment response and prognosis. When the number of MTX treatment cycles increases, the therapeutic effect and prognosis of PCNSL patients are improved. The patients treated with MTX-based triplet combination regimens have a better ORR and CR. Although HD-MTX is generally well tolerated, it is necessary to be cautious about the use of multiple therapy that includes cytarabine to prevent potential acute toxicity.

The contemporary spectrum of radiotherapy for hematologic malignancies involving the central nervous system: From focal therapy to craniospinal

The contemporary landscape of systemic therapy options for hematologic malignancies involving the central nervous system (CNS-HM) is rapidly evolving; a key question is how radiotherapy (RT) can be optimally integrated to improve patient outcomes. Historically, use of RT to treat CNS-HM was defined by broad fields and high doses. While effective, this approach raised concerns of potential neurotoxicity which significantly decreased RT utilization. RT was replaced by high-dose, CNS-penetrant, systemic therapies that offered durable control with lower perceived neurotoxic risk. But, as the therapeutic toolbox for CNS-HM expands, so too does the complexity and diversity of potential clinical scenarios where RT should be considered. In this review, we describe both well-established and emerging opportunities for RT integration, emphasizing how dose selection and field design could balance neurotoxicity risk and disease control. We propose an anatomical framework that captures the diverse utilization of RT for CNS-HM and serves as a practical guide for RT volume and dose design.

Clinical characteristics and survival outcomes of patients with primary central nervous system lymphoma treated with high-dose methotrexate-based polychemotherapy and consolidation therapies

Given the rarity of primary central nervous system lymphoma (PCNSL), evaluations of different high-dose methotrexate-(HD-MTX)-based treatment regimens is sparse. This retrospective, multicenter study evaluates clinical characteristics and outcomes (progression-free, overall and disease-specific survival) after five HD-MTX-based polychemotherapeutic regimens and two consolidation therapies. 346 patients with histologically confirmed PCNSL, treated with ≥ 1 cycle HD-MTX-based strategies (≥3g/m2/cycle) were included. The regimens included MATRIX (HD-MTX, HD-AraC, thiotepa, and rituximab), (R)MBVP±HD-AraC (HD-MTX, teniposide/etoposide, carmustine, prednisolone, ± HD-AraC, ± rituximab), (R)MP (HD-MTX, procarbazine, ± rituximab), and a combination of HD-MTX and HD-AraC. The overall response rate after induction was 69 %, 28 % complete remission and progressive disease was observed in 100 (29 %) patients. 126 (36 %) patients received consolidation, including high-dose-BCNU-thiotepa with autologous stem cell transplantation (HD-BCNU-TT/ASCT, n = 59 (17 %)) or whole brain radiotherapy (WBRT, n = 67 (19 %)). Clinical characteristics associated with adverse mortality risk by multivariable prognostication contained age > 60 years (HR 1.61, p = 0.011), elevated LDH (HR 1.75, p = 0.004) and WHO status ≥ 2 (HR 1.56, p = 0.010). Independently, induction regimens containing HD-AraC demonstrated survival benefit compared to induction regimens without HD-AraC (HR 0.59, p = 0.002). Without preference for HD-BCNU-TT/ASCT or WBRT, a favorable effect of consolidation (HR 0.44 and HR 0.42, p < 0.001) was confirmed, also with consolidation as time-dependent variable. Competing risk analysis showed similar low incidence of lymphoma-unrelated deaths in consolidated and unconsolidated patients. This study confirms that age, elevated LDH and WHO status increase the mortality risk. HD-AraC containing treatment regimens and consolidation with HD-BCU-TT/ASCT or WBRT were associated with superior survival, including a favorable low incidence of lymphoma-unrelated deaths.

Novel Therapies for Primary Central Nervous System Lymphomas

PURPOSE OF REVIEW

Primary Central Nervous System Lymphoma (PCNSL) is an aggressive form of lymphoma that can involve the brain, spinal cord, leptomeninges and eyes. PCNSL prognosis continues to be poor, with 5-year survival rates of 30-40%. Therapeutic options are especially limited for relapsed/refractory (r/r) PCNSL. In recent years, studies shed light on the pathogenesis and oncogenic pathways driving PCNSL, leading to the development of novel therapeutics. In this review, we discuss the evidence supporting these novel agents and present ongoing clinical studies.

RECENT FINDINGS

Key oncogenic drivers of PCNSL include activation of the NFkB pathway, cell cycle dysregulation, somatic hypermutation and immune evasion, leading to the investigation of targeted therapeutics and immunotherapeutics to inhibit these pathways. Such approaches include BTK inhibitors, mTOR/PI3K inhibitors, immunomodulatory agents (IMIDs), immune checkpoint inhibitors and CD19-based CAR T-cells. The therapeutic repertoire for PCNSL is rapidly evolving, and a multi-modality approach including intensive chemotherapy regimens and novel therapies will likely be utilized in the future.

The Baseline Pan-Immune‑Inflammation Value (PIV) and PILE in Predicting Clinical Outcomes and Therapeutic Response for Primary Central Nervous System Lymphoma

Purpose

To investigate the prognostic significance of pan-immune-inflammation value (PIV) and PILE score (based on PIV, lactate dehydrogenase (LDH), and Eastern Cooperative Oncology Group Performance Status (ECOG PS)) in patients with primary central nervous system lymphoma (PCNSL).

Patients and Methods

A total of 109 patients were enrolled. PIV was calculated as follows: (neutrophil count × platelet count × monocyte count)/lymphocyte count. The PILE score was incorporated based on PIV, LDH levels, and ECOG PS. The Kaplan-Meier curves and Cox hazards regression models were applied for survival analyses. The relationship between PIV, PILE, and therapeutic response was examined.

Results

Baseline high PIV was significantly associated with worse overall survival (OS) in univariate (HR 3.990, 95% CI 1.778-8.954, p < 0.001) and multivariate (HR 3.047, 95% CI 1.175-7.897, p = 0.022) analyses. High PIV was also associated with worse progression-free survival (PFS) in univariate (HR 2.121, 95% CI 1.075-4.186, p = 0.030) but not significant in multivariate analyses. PIV outperformed other systemic inflammation parameters. The patients in the high PILE group (PILE score 2-3) had worse OS (p = 0.008) and PFS (p < 0.001) compared to the low PILE group (PILE score 0-1). PILE was independently associated with therapeutic response to initial treatment (OR 0.17, 95% CI 0.05-0.46; p < 0.001).

Conclusion

High PIV and PILE were correlated with worse clinical outcomes in PCNSL patients, indicating that PIV and PILE might be a powerful predictor of prognosis and a potential predictive indicator for therapeutic response in PCNSL.

Patterns of Treatment Failure in Primary Central Nervous System Lymphoma

OBJECTIVES

Progression of PCNSL remains a challenge with salvage therapies, including the risk of substantial morbidity and mortality. We report patterns of first tumor progression to inform opportunities for improvement.

METHODS

This is an institutional retrospective review from 2002 to 2021 of 95 consecutive patients with pathologically confirmed PCNSL, of whom 29 experienced progressive disease. Kaplan-Meier method, log-rank test, and Cox proportional hazard models are used to characterize associations of patient, tumor, and treatment variables with LC, PFS, and patterns of first failure.

RESULTS

Most patients were below 65 years old (62%) with KPS >70 (64%) and negative CSF cytology (70%). In 70 patients with MRIs, the median tumor volume was 12.6 mL (range: 0.5 to 67.8 mL). After a median follow-up of 11 months, 1-year PFS was 48% and 1-year LC was 80%. Of the 29 patients with progression, 24% were distant only, 17% were distant and local, and 59% were local only. On MVA, LC was associated with age (HR: 1.08/y, P =0.02), KPS (HR: 0.10, P =0.02), completion of >6 cycles of HD-MTX (HR: 0.10, P <0.01), and use of intrathecal chemotherapy (HR: 0.03, P <0.01). On UVA, local only first failure trended to be increased with >14 mL tumors (OR: 5.06, P =0.08) with 1-year LC 83% (<14 mL) versus 64% (>14mL). There were no significant associations with LC and WBRT ( P =0.37), Rituximab ( P =0.12), or attempted gross total resection ( P =0.72).

CONCLUSIONS

Our findings reaffirm the importance of systemic and intrathecal therapies for local control in PCNSL. However, bulky tumors trend to fail locally, warranting further investigation about the role of local therapies or systemic therapy intensification.

Machine learning-based pathomics signature of histology slides as a novel prognostic indicator in primary central nervous system lymphoma

PURPOSE

To develop and validate a pathomics signature for predicting the outcomes of Primary Central Nervous System Lymphoma (PCNSL).

METHODS

In this study, 132 whole-slide images (WSIs) of 114 patients with PCNSL were enrolled. Quantitative features of hematoxylin and eosin (H&E) stained slides were extracted using CellProfiler. A pathomics signature was established and validated. Cox regression analysis, receiver operating characteristic (ROC) curves, Calibration, decision curve analysis (DCA), and net reclassification improvement (NRI) were performed to assess the significance and performance.

RESULTS

In total, 802 features were extracted using a fully automated pipeline. Six machine-learning classifiers demonstrated high accuracy in distinguishing malignant neoplasms. The pathomics signature remained a significant factor of overall survival (OS) and progression-free survival (PFS) in the training cohort (OS: HR 7.423, p < 0.001; PFS: HR 2.143, p = 0.022) and independent validation cohort (OS: HR 4.204, p = 0.017; PFS: HR 3.243, p = 0.005). A significantly lower response rate to initial treatment was found in high Path-score group (19/35, 54.29%) as compared to patients in the low Path-score group (16/70, 22.86%; p < 0.001). The DCA and NRI analyses confirmed that the nomogram showed incremental performance compared with existing models. The ROC curve demonstrated a relatively sensitive and specific profile for the nomogram (1-, 2-, and 3-year AUC = 0.862, 0.932, and 0.927, respectively).

CONCLUSION

As a novel, non-invasive, and convenient approach, the newly developed pathomics signature is a powerful predictor of OS and PFS in PCNSL and might be a potential predictive indicator for therapeutic response.

Prognostic factors for primary diff use large B-cell lymphoma of the brain

OBJECTIVE

Diffuse large B-cell lymphoma (DLBCL) is the most common histopathological type of non-Hodgkin's lymphoma and might arise from various extranodal sites. Little is known about the clinical characteristics and survival outcomes of primary DLBCL of the brain, including the cerebrum, cerebellum, brain steam and ventricle (CCSV). Thus, we performed this study to explore the independent prognostic factors of CCSV-DLBCL using the Surveillance, Epidemiology, and End Results (SEER) database.

MATERIALS AND METHODS

We extracted the data of patients diagnosed with CCSV-DLBCL between 1975 and 2016 from the SEER database. Variables including demographic characteristics, Ann Arbor stage and therapies, such as surgery, radiation and chemotherapy, were all collected. The prognostic factors on overall survival (OS) and disease-specific survival (DSS) were analysed using Kaplan-Meier curves.

RESULTS

One thousand three hundred and twenty-eight patients were finally enrolled in the analysis. The median age was 62 years old. More than half of the cases of CCSV-DLBCL (54.22%) originated from the cerebrum. Patients older than 75 years had the worst OS and DSS. Moreover, black people had the worst survival outcomes compared with white and other people. Surgery, radiation and chemotherapy all significantly improved OS and DSS.

CONCLUSION

To the best of our knowledge, this is the largest population-based study of CCSV-DLBCL. Advanced age, black race, lack of surgical resection, radiation or chemotherapy were all poor prognostic factors.

First-line induction chemotherapy with high-dose methotrexate versus teniposide in patients with newly diagnosed primary central nervous system lymphoma: a retrospective, multicenter cohort study

BACKGROUND

This study aimed to compare the efficacy and safety of high-dose methotrexate (HD-MTX) versus teniposide (TEN) in patients with newly diagnosed immunocompetent primary central nervous system lymphomas (PCNSLs).

METHODS

The study included immunocompetent, adult patients with newly diagnosed PCNSL at 22 centers in China from 2007 to 2016. The patients received HD-MTX or TEN as first-line induction therapy. The objective response rate, progression-free survival, and overall survival were analyzed for each patient cohort.

RESULTS

A total of 96 patients were eligible: 62 received HD-MTX, while 34 received teniposide. The overall response rate was 73.2% and 72.7% in the MTX and the TEN cohorts, respectively (P = 0.627). The median progression-free survival was 28.4 months [95% confidence interval (CI): 13.7-51.2] in the MTX cohort and 24.3 months (95% CI: 16.6-32.1) in the TEN cohort (P = 0.75). The median overall survival was 31 months (95% CI: 26.8-35.2) in the MTX cohort and 32 months (95% CI: 27.6-36.4) in the TEN cohort (P = 0.77). The incidence of any grade of coagulopathy/deep-vein thrombosis and gastrointestinal disorders was significantly higher in the MTX cohort than in the TEN cohort; no significant difference was found in the incidence of other adverse events between the two cohorts.

CONCLUSIONS

This was the first multicenter study using TEN as the main agent compared with HD-MTX in newly diagnosed primary CNS lymphoma. The TEN-based regimen was non-inferior to the HD-MTX-based regimen with similar overall responses.

CLASSIFICATION OF EVIDENCE

This study provided Class III evidence that the teniposide-based regimen was non-inferior to high-dose methotrexate - based regimen with similar overall responses and long-time survival in immunocompetent patients with PCNSL.

Challenges in the management of primary central nervous system lymphoma

Primary central nervous system lymphoma (PCNSL) is a rare extranodal non-Hodgkin lymphoma. Stereotactic biopsy remains the gold standard for the pathological diagnosis of PCNSL. However, certain new auxiliary diagnostic methods are considered to have good application prospects; these include cytokine and tumor circulating DNA, among others. Although new drugs such as immunomodulators, immune checkpoint inhibitors, chimeric antigen receptor T-cells, and Bruton tyrosine kinase inhibitors have brought hope owing to their improved efficacy, the high recurrence rate and subsequent high mortality remain barriers to long-term survival. Increasing emphasis is therefore being placed on consolidation treatments. Consolidation treatment strategies include whole brain radiotherapy, autologous hematopoietic stem cell transplantation, and non-myeloablative chemotherapy. As studies directly comparing the effectiveness and safety of different consolidation treatment schemes are lacking, the optimal consolidation strategy remains uncertain. This article will review the diagnosis and treatment of PCNSL, focusing on the progress in research pertaining to consolidation therapy.

Autologous hematopoietic cell transplantation versus whole-brain radiotherapy consolidation in primary central nervous system lymphoma: A systematic review and meta-analysis

The management of newly diagnosed primary central nervous system lymphoma (PCNSL) includes administration of high-dose methotrexate based regimens followed by consolidation therapy to minimize the risk of relapse. However, the best consolidation strategy (autologous hematopoietic cell transplant [auto-HCT] vs. whole-brain radiotherapy [WBRT]) is controversial. Hence, we performed a systematic review and meta-analysis of all randomized controlled trials that compared auto-HCT versus WBRT consolidation for patients with PCNSL after first-line treatment.The primary outcome was overall survival (OS), while the secondary outcomes included progression-free survival (PFS), response rates (overall response rate [ORR] and complete remission [CR]), relapse rate, treatment-related mortality (TRM), and neuropsychological adverse events. We performed a pooled analysis of the single-arm studies that incorporated auto-HCT or WBRT consolidation and evaluated neurocognitive outcomes. Only two studies met the inclusion criteria (n = 240). There was no significant difference in OS (HR = 1.50; 95% CI = 0.95-2.36), PFS (HR = 0.99; 95% CI = 0.44-2.22), ORR (RR = 1.48; 95% CI = 0.90-2.44), CR rate (RR = 1.21; 95% CI = 0.90-1.63), relapse rate (RR = 0.46; 95% CI = 0.05-4.28), and TRM (RR = 5.67; 95% CI = 1.01-31.91). The neuropsychological tests to assess neurocognitive domains were different and inconsistently reported in the two studies and therefore we were unable to perform a meta-analysis but provide a descriptive assessment. Both the studies showed a significant decline in the attention/executive function (based on the trail making test A and trail making test B) in those receiving WBRT compared to auto-HCT. We found 9 single-arm phase II studies that reported data on outcomes associated with either auto-HCT (5 studies) or WBRT (4 studies) consolidation. Of these, two studies (n = 43) reported data on neurocognitive decline following auto-HCT consolidation. Pooled proportion of patients with neurocognitive decline in these studies was 6% (95% CI, 0%-17%) for those receiving auto-HCT and there was no heterogeneity between studies (I²  = 0%). Three studies (n = 122) reported data on neurocognitive decline following WBRT consolidation. Pooled proportion of patients with neurocognitive decline in these studies was 43% (95% CI, 11%-78%) for those receiving WBRT and there was high heterogeneity between studies (I²  = 94%). There was significant heterogeneity between subgroups (p = 0.035). The outcomes were not significantly different in patients with PCNSL receiving auto-HCT or WBRT consolidation therapies, however, there is a higher degree of neurocognitive decline associated with WBRT compared to auto-HCT consolidation. The decision to choose a consolidation strategy needs to be individualized based on age, frailty, and co-morbidities.

European Association of Neuro-Oncology (EANO) guidelines for treatment of primary central nervous system lymphoma (PCNSL)

The management of primary central nervous system (PCNSL) is one of the most controversial topics in neuro-oncology because of the complexity of the disease and the limited number of controlled studies available. In 2021, given recent advances and the publication of practice-changing randomized trials, the European Association of Neuro-Oncology (EANO) created a multidisciplinary task force to update the previously published evidence-based guidelines for immunocompetent adult patients with PCNSL and added a section on immunosuppressed patients. The guideline provides consensus considerations and recommendations for the treatment of PCNSL, including intraocular manifestations and specific management of the elderly. The main changes from the previous guideline include strengthened evidence for the consolidation with ASCT in first-line treatment, prospectively assessed chemotherapy combinations for both young and elderly patients, clarification of the role of rituximab even though the data remain inconclusive, of the role of new agents, and the incorporation of immunosuppressed patients and primary ocular lymphoma. The guideline should aid the clinicians in everyday practice and decision making and serve as a basis for future research in the field.

Radiotherapy or chemotherapy: a real-world study of the first-time relapsed and refractory primary central nervous system lymphoma

Background

Primary central nervous system lymphoma (PCNSL) is an uncommon variant of non-Hodgkin lymphoma (NHL) with high aggressiveness and poor prognosis. Although complete remission (CR) could be achieved with therapy, some patients remain refractory or recurrently with a worse response to salvage treatment and poor prognosis. No consensus on rescue therapy has been established currently. This study is aimed to evaluate the efficacy of radiotherapy or chemotherapy in first-time relapsed or refractory progressed PCNSL (R/R PCNSL) and analysis the prognostic factors, to explore differences between relapsed and refractory PCNSL.

Methods

Totally 105 R/R PCNSL patients from Huashan Hospital between 1 January 2016 and 31 December 2020 were enrolled, underwent salvage radiotherapy or chemotherapy and received response assessments after each course. PFS1 was defined as the time from diagnosis to the first time of recurrence or refractory progression. Statistical analysis was performed with SPSS version 26.0.

Results

Response and survival were analyzed over a 17.5months (median) follow-up. Compared to relapsed PCNSL (n = 42), refractory PCNSL (n = 63) had a shorter median PFS1 related to deep lesions. 82.4% of cases were discovered as the second relapse or progression. ORR and PFS were both higher in relapsed PCNSL than those in refractory PCNSL. ORR of radiotherapy in both relapsed and refractory PCNSL was higher than that of chemotherapy. Elevated CSF protein and ocular involvement were related to PFS and OS after recurrence respectively in relapsed PCNSL. Age ≥ 60y was unfavorable to OS-R (OS after recurrence or progression) in refractory PCNSL.

Conclusions

Our results indicate that relapsed PCNSL responds well to inducing and salvage therapy and has a better prognosis compared to refractory PCNSL. Radiotherapy is effective for PCNSL after the first relapse or progression. Age, CSF protein level, and ocular involvement could be potential factors to predict prognosis.

The role of radiotherapy in newly diagnosed primary CNS lymphoma: A descriptive review and a pragmatic approach to clinical practice

Earlier, prior to the development of effective systemic therapy, monotherapy with whole-brain radiotherapy (WBRT) was widely used to treat primary central nervous system lymphoma (PCNSL). Recently, chemotherapy, especially with high dose methotrexate (HDMTX), has largely replaced WBRT as upfront treatment, and the most accepted standard of care is induction with a combination drug therapy followed by consolidation therapy with either autologous stem-cell transplantation (ASCT) or radiation. Whilst WBRT is an effective component of treatment, it is occasionally associated with risk of permanent, irreversible neurotoxicity when doses of more than 30 Gy are used. Hence, there has been a strong focus on the optimization of radiotherapy (RT) which includes dose reduction in the consolidation phase. In this comprehensive review, we have summarized the progress on clinical results and evidence considering the role and use of radiation including combined treatment modalities, low-dose radiotherapy, and neurotoxicity. Finally, we present a practical approach to low-dose WBRT and boosting higher doses to the gross tumor that can be integrated into clinical practice.

Randomized phase III study of high-dose methotrexate and whole-brain radiotherapy with/without temozolomide for newly diagnosed primary CNS lymphoma: JCOG1114C

BACKGROUND

The goal was to determine whether the addition of temozolomide (TMZ) to the standard treatment of high-dose methotrexate (HD-MTX) and whole-brain radiotherapy (WBRT) for primary central nervous system lymphoma (PCNSL) improves survival.

METHODS

An open-label, randomized, phase III trial was conducted in Japan, enrolling immunocompetent patients aged 20-70 years with histologically confirmed, newly diagnosed PCNSL. After administration of HD-MTX, patients were randomly assigned to receive WBRT (30 Gy) ± 10 Gy boost (arm A) or WBRT ± boost with concomitant and maintenance TMZ for two years (arm B). The primary endpoint was overall survival (OS).

RESULTS

Between September 29, 2014 and October 15, 2018, 134 patients were enrolled, of whom 122 were randomly assigned and analyzed. At the planned interim analysis, two-year OS was 86.8% (95% confidence interval [CI]: 72.5-94.0%) in arm A and 71.4% (56.0-82.2%) in arm B. The hazard ratio was 2.18 (95% CI: 0.95 to 4.98), with the predicted probability of showing the superiority of arm B at the final analysis estimated to be 1.3%. The study was terminated early due to futility. O 6-methylguanine-DNA methyltransferase (MGMT) promoter methylation status was measured in 115 tumors, and it was neither prognostic nor predictive of TMZ response.

CONCLUSIONS

This study failed to demonstrate the benefit of concomitant and maintenance TMZ in newly diagnosed PCNSL.

Evidence-based expert consensus on the management of primary central nervous system lymphoma in China

Primary central nervous system lymphoma (PCNSL) is a type of central nervous system restricted non-Hodgkin lymphoma, whose histopathological diagnosis is majorly large B cell lymphoma. To provide specific, evidence-based recommendations for medical professionals and to promote more standardized, effective and safe treatment for patients with PCNSL, a panel of experts from the Chinese Neurosurgical Society of the Chinese Medical Association and the Society of Hematological Malignancies of the Chinese Anti-Cancer Association jointly developed an evidence-based consensus. After comprehensively searching literature and conducting systematic reviews, two rounds of Delphi were conducted to reach consensus on the recommendations as follows: The histopathological specimens of PCNSL patients should be obtained as safely and comprehensively as possible by multimodal tomography-guided biopsy or minimally invasive surgery. Corticosteroids should be withdrawn from, or not be administered to, patients with suspected PCNSL before biopsy if the patient's status permits. MRI (enhanced and DWI) should be performed for diagnosing and evaluating PCNSL patients where whole-body PET-CT be used at necessary time points. Mini-mental status examination can be used to assess cognitive function in the clinical management. Newly diagnosed PCNSL patients should be treated with combined high-dose methotrexate-based regimen and can be treated with a rituximab-inclusive regimen at induction therapy. Autologous stem cell transplantation can be used as a consolidation therapy. Refractory or relapsed PCNSL patients can be treated with ibrutinib with or without high-dose chemotherapy as re-induction therapy. Stereotactic radiosurgery can be used for PCNSL patients with a limited recurrent lesion who were refractory to chemotherapy and have previously received whole-brain radiotherapy. Patients with suspected primary vitreoretinal lymphoma (PVRL) should be diagnosed by vitreous biopsy. PVRL or PCNSL patients with concurrent VRL can be treated with combined systemic and local therapy.

High-dose methotrexate and rituximab induction regimen in immunocompetent patients with primary CNS lymphoma: a retrospective single-center study of survival predictors

PURPOSE

Primary Central Nervous System Lymphoma (PCNSL) is an aggressive tumor that is confined to the CNS. Although the provision of high-dose methotrexate (HD-MTX) has remarkably improved outcomes in PCNSL patients, the optimal treatment regimens and standard MTX dose for induction therapy have been largely controversial. Herein, we sought to explore the impact of adjuvant rituximab and different dosages of induction HD-MTX on survival outcomes of immunocompetent patients with PCNSL.

METHODS

In this study, we examined patients with PCNSL treated at a single NCI-designated comprehensive cancer center to evaluate their survival outcomes. We conducted a retrospective analysis of 51 immunocompetent patients with PCNSL who received their induction chemotherapy at the University of Alabama at Birmingham (UAB) between 2001 and 2019. Only adult patients with a confirmed diagnosis of PCNSL who had either HD-MTX alone or in combination with rituximab were included. Patients' demographics, clinical characteristics, and survival data were collected and analyzed.

RESULTS

There is no significant difference in survival among patients who received MTX alone versus MTX plus rituximab (HR = 0.996 (95% CI: 0.398-2.493), p = 0.994). Lower doses of MTX were associated with worse survival outcomes (HR = 0.680 (95% CI: 0.530-0.872), p = 0.002); however, this difference in survival was not significant when adjusted to age (HR = 0.797 (95% CI: 0.584-1.088), p = 0.153).

CONCLUSION

Our experience challenges the role of rituximab in PCNSL during induction therapy. Our study also highlights the shorter survival in elderly patients with PCNSL which can be related, to some extent, to the relatively lower doses of HD-MTX. There is an unmet need to establish a consensus on the most effective upfront regimen in PCNSL through prospective studies.

Efficiency of antioxidant Avenanthramide-C on high-dose methotrexate-induced ototoxicity in mice

Methotrexate (MTX) has been used in treating various types of cancers but can also cause damage to normal organs and cell types. Folinic acid (FA) is a well-known MTX antidote that protects against toxicity caused by the drug and has been used for decades. Since hearing loss caused by MTX treatment is not well studied, herein we aimed to investigate the efficiency of the antioxidant Avenanthramide-C (AVN-C) on high-dose MTX (HDMTX) toxicity in the ear and provide insights into the possible mechanism involved in MTX-induced hearing loss in normal adult C57Bl/6 mice and HEI-OC1 cells. Our results show that the levels of MTX increased in the serum and perilymph 30 minutes after systemic administration. MTX increased hearing thresholds in mice, whereas AVN-C and FA preserved hearing within the normal range. MTX also caused a decrease in wave I amplitude, while AVN-C and FA maintained it at higher levels. MTX considerably damaged the cochlear synapses and neuronal integrity, and both AVN-C and FA rescued the synapses. MTX reduced the cell viability and increased the reactive oxygen species (ROS) level in HEI-OC1 cells, but AVN-C and FA reversed these changes. Apoptosis- and ROS-related genes were significantly upregulated in MTX-treated HEI-OC1 cells; however, they were downregulated by AVN-C and FA treatment. We show that MTX can cause severe hearing loss; it can cross the blood–labyrinth barrier and cause damage to the cochlear neurons and outer hair cells (OHCs). The antioxidant AVN-C exerts a strong protective effect against MTX-induced ototoxicity and preserved the inner ear structures (synapses, neurons, and OHCs) from MTX-induced damage. The mechanism of AVN-C against MTX suggests that ROS is involved in HDMTX-induced ototoxicity.

Revisiting the concept of recurrence of primary CNS lymphomas after complete response to methotrexate-based therapy: Periventricular reseeding as the predominant mechanism of recurrence

Purpose

Understanding patterns of relapse for primary central nervous system lymphoma (PCNSL) may inform mechanisms of recurrence and optimal consolidation strategies. In this study, we report patterns of relapse among patients with PCNSL who achieved a complete response to high-dose methotrexate (HD-MTX)-based chemotherapy with or without consolidation radiation therapy (RT).

Methods and Materials

We conducted an institutional retrospective analysis of patients with PCNSL who received HD-MTX-based chemotherapy between November 2001 and May 2019. Relapses were characterized as in-field (within original T1 contrasted lesion), marginal (within T2 fluid-attenuated inversion recovery but not T1), local (in-field or marginal), distant brain (no overlap), or distant (distant brain, cerebrospinal fluid, vitreous or extra-axial) and further characterized with respect to periventricular location (≤10 mm of ventricles).

Results

Seventy-eight patients with PCNSL met inclusion criteria, of whom 29 (37%) underwent consolidation RT. Median progression-free survival and overall survival were 57.0 and 66.7 months, respectively. After a median follow-up of 38.9 months, a total of 32 patients (41%) experienced recurrence. Most patients (21 [65.6%]) had a periventricular failure. Surprisingly, local recurrences (n = 11) were exclusively observed within periventricular lesions, whereas distant recurrences (n = 21) were seen in both periventricular and nonperiventricular locations (P = .009). The median time to progression was shorter for locally recurrent lesions compared with distant recurrences (13.8 vs 26.1 months; P = .03).

Conclusions

After complete response to HD-MTX, few failures occurred within initial T1 contrast-enhancing lesions and many of these may have been alternatively classified as periventricular failures. These observations argue against the use of purely focal RT consolidation for patients who achieve a complete response after HD-MTX-based chemotherapy and suggest that periventricular reseeding may have a central role in PCNSL recurrence.

First-line high-dose therapy and autologous blood stem cell transplantation in patients with primary central nervous system non-Hodgkin lymphomas—a single-centre experience in 61 patients

Primary central nervous system non-Hodgkin lymphomas (PCNS-NHLs) are extranodal B-cell lymphomas with poor prognosis. The role of high-dose therapy (HDT) followed by autologous blood stem cell transplantation (ASCT) as first-line therapy is still not clear. We retrospectively collected long-term follow up data of 61 consecutive patients with PCNS-NHL at the University Hospital Düsseldorf from January 2004 to December 2016. Thirty-six patients were treated with conventional chemoimmunotherapy (cCIT) only (CT-group). Seventeen patients received an induction cCIT followed by HDT and ASCT. In the CT-group, the overall response rate (ORR) was 61% (CR 47%, PR 14%), and there were 8% treatment-related deaths (TRD). Progression-free survival (PFS) was 31.8 months, and overall survival (OS) was 57.3 months. In the HDT-group, the ORR was 88% (59% CR, 29% PR), and there were 6% TRD. Median PFS and OS were not reached at 5 years. The 5-year PFS and OS were 64.7%. After a median follow up of 71 months, 10 patients (59%) were still alive in CR/PR following HDT and ASCT, one patient was treated for progressive disease (PD), and 7 had died (41%, 6 PD, 1 TRD). All patients achieving CR prior to HDT achieved durable CR. In the CT-group, 8 patients (22%) were alive in CR/PR after a median follow-up of 100 months. Twenty-eight patients died (78%, 24 PD, 2 TRD, 2 deaths in remission). In the univariate analysis, the HDT-group patients had significantly better PFS (not reached vs 31.8 months, p = 0.004) and OS (not reached vs 57.3 months, p = 0.021). The multivariate analysis showed HDT was not predictive for survival. Treatment with HDT + ASCT is feasible and offers the chance for long-term survival with low treatment-related mortality in younger patients. In this analysis, ORR, PFS and OS were better with HDT than with conventional cCIT alone. This result was not confirmed in the multivariate analysis, and further studies need to be done to examine the role of HDT in PCNSL.

Primary Central Nervous System Lymphomas

Primary central nervous system lymphoma is a rare and aggressive extranodal non-Hodgkin lymphoma restricted to the brain, spinal cord, cerebrospinal fluid, and eyes. Optimization of treatment including high-dose methotrexate-based chemotherapy followed by consolidation therapy in the form of autologous stem cell transplant or whole-brain radiation leads to improved survival. However, several patients do not respond to upfront therapy and the relapse risk is high. Additionally, there is a risk of delayed neurotoxicity, particularly in older patients. Recent molecular insights underlying the pathophysiology of PCNSL have led to the development of clinical trials involving targeted therapies and immunotherapies for salvage.

Primary treatment and recent survival trends in patients with primary diffuse large B-cell lymphoma of central nervous system, 1995-2016: A population-based SEER analysis

This retrospective cohort study aimed to evaluate primary treatment and recent survival trends in patients with primary diffuse large B-cell lymphoma of central nervous system (CNS) from 1995 to 2016. Using the SEER data, patients diagnosed with non-HIV-associated primary central nervous system lymphoma (PCNSL)-diffuse large B-cell lymphoma (DLBCL) aged ⩾18 years between 1995 and 2016 were identified. The year of diagnosis was divided into the time period-1 (1995-2002), the time period-2 (2003-2012), and the time period-3 (2013-2016). Chi-square tests, the Kaplan-Meier method, log-rank test, and Cox regression model were used in the analysis. Overall, 3760 patients were included. Both the use of radiotherapy alone and the application of combined chemoradiotherapy decreased significantly, following the wider use of chemotherapy alone during 1995-2016. There was a significant improvement in PCNSL cause-specific survival (CSS) (period-1: 13 months vs. period-2: 19 months vs. period-3: 41 months, p < 0.001). Survival of patients aged above 70 years did not change from the time period-1 to the time period-2 (p = 0.101). However, there was an increase in CSS from the time period-2 to the time period-3 in the elderly patients (period-2: 5 months vs. period-3: 9 months, p < 0.001). On multivariable analyses, diagnosed in the time period-3 was significantly and independently associated with better CSS (hazard ratio 0.577, 95% confidence interval 0.506-0.659, p < 0.001). Our analysis shows the use of radiotherapy in the treatment of PCNSL has waned over the study span. There was a significant improvement in CSS during 1995-2016, which reflected developments in treatment over time. The elderly patient population also gained a significant CSS benefit in the most recent period.

A Novel Prognostic Marker for Primary CNS Lymphoma: Lactate Dehydrogenase-to-Lymphocyte Ratio Improves Stratification of Patients Within the Low and Intermediate MSKCC Risk Groups

Background

Primary central nervous system lymphoma (PCNSL) is a highly aggressive and rare extranodal non-Hodgkin lymphoma (NHL). The MSKCC and the IELSG scores represent the most widely used prognostic models, but many changes have occurred in therapeutic protocols since their development. Moreover, many PCNSL patients cannot be classified using the IELSG score. We thus aimed to create a novel, effective and feasible prognostic model for PCNSL.

Methods

We included 248 PCNSL patients diagnosed with PCNSL. Our primary endpoint was the overall survival (OS) and we used the receiver operating characteristic (ROC) analysis to determine the optimal prognostic cut-off value for LLR (lactate dehydrogenase-to-lymphocyte ratio), neutrophil-to-lymphocyte ratio (NLR) and derived neutrophil-to-lymphocyte ratio (dNLR). Variable associated with OS were evaluated by univariate and multivariate analyses. 124 out of 248 patients were randomly selected as the internal validation cohort.

Results

By univariate analysis, an age >60 years, Eastern Cooperative Oncology Group performance status (ECOG PS) >1, treatment with radiotherapy alone, high-risk groups of Memorial Sloan Kettering Cancer Center (MSKCC) score, NLR >4.74, dNLR >3.29, and LLR >166.8 were significantly associated with a worse OS. By multivariate analysis, the MSKCC score and LLR were confirmed as independent prognostic parameters for poorer OS. OS, however, was not significantly different between low- and intermediate-risk groups according to the MSKCC score, while LLR proved to be prognostically relevant and was thus used to develop a novel, effective three-tier PCNSL scoring system. Of 124 patients, 84 patients with survival data and LLR data were successfully validated by newly established PCNSL LLR scoring system.

Conclusions

In the present study, we demonstrate that a high LLR represents an independent unfavorable prognostic parameter in PCNSL patients which can be integrated into an effective prognostic model.

Outcome of patients with newly diagnosed primary CNS lymphoma after high-dose methotrexate followed by consolidation whole-brain radiotherapy and cytarabine: an 8-year cohort study

BACKGROUND

Addition of cytarabine to high-dose methotrexate (HD-MTX) chemotherapy improves outcome of primary CNS lymphoma (PCNSL); however, the combination therapy increases toxicity. Sequential chemotherapy and cranial radiation may decrease toxicity without altering efficacy.

METHODS

This was a single-center, retrospective cohort study of consecutive newly diagnosed immunocompetent PCNSL patients treated with HD-MTX (5 cycles of 3 g/m² every 2 weeks) followed by consolidation whole-brain radiotherapy (WBRT) and cytarabine (2 cycles of 3 g/m²/d for 2 days every 3 weeks) from January 2013 to December 2020. Initial WBRT before HD-MTX was allowed in patients with significant disability or brain edema at presentation. Primary outcome was progression-free survival (PFS). Key secondary outcomes were response rate, treatment-related toxicity, and overall survival (OS).

RESULTS

Of 41 patients, 25 patients had a complete response (CR) and ten patients had a partial response, inferring an overall response rate (ORR) of 85.4% and a CR rate of 60.9%. More than 90% of patients were able to tolerate and complete the HD-MTX. The incidence of ≥ grade 3 hematologic and non-hematologic toxicities were 4.8% and 17.1%, respectively. Treatment-related mortality rate was 2.4%. There was no difference in toxicity between patients with age < 60 and ≥ 60 years. At the median follow-up duration of 39.8 months, the median PFS was 35.2 months (95% CI 12.4-69.3) and median OS was 46.5 months (95% CI 21.8-NR).

CONCLUSION

High-dose methotrexate followed by consolidation whole-brain radiotherapy and cytarabine has acceptable efficacy, great tolerability, and low toxicity in newly diagnosed PCNSL patients.

Central Nervous System Lymphoma: Approach to Diagnosis and Treatment

Central nervous system lymphoma (CNSL) is a rare form of extranodal non-Hodgkin lymphoma. Central nervous system lymphoma can be primary (isolated to the central nervous space) or secondary in the setting of systemic disease. Treatment of CNSL has improved since the introduction of high-dose methotrexate and aggressive consolidation regimens. However, results after treatment are durable in only half of patients, and long-term survivors may experience late neurotoxicity, impacting quality of life. Given the rarity of this disease, few randomized prospective trials exist. This leaves many questions unanswered regarding optimal first-line and salvage treatments. Recent advances in the knowledge of pathophysiology of CNSL will hopefully help the development of future treatments. This review gives an overview of the epidemiology, pathophysiology, clinical presentation, diagnosis, and treatment of immunocompetent patients with CNSL.

The Role of Rituximab in the Treatment of Primary Central Nervous System Lymphoma

Simple Summary

Primary central nervous system lymphoma (PCNSL) is a rare form of cancer and the treatment of newly diagnosed patients is challenging. Many chemotherapy regimens are being used, and methotrexate is an important component in most. The role of the immunotherapy rituximab is not as clear. This review focuses on the available evidence for the use of this monoclonal antibody in the treatment of patients with PCNSL.

Abstract

Primary central nervous system lymphoma (PCNSL) is a type of non-Hodgkin lymphoma limited to the central nervous system. It has a poor prognosis. Consensus has been reached on the treatment of newly diagnosed patients with high-dose methotrexate-based chemotherapy, but whether the addition of the monoclonal anti-CD20 antibody rituximab improves survival, as it does in systemic B-cell non-Hodgkin lymphoma, remains disputed. In this review, we reflect on the available evidence of the use of rituximab in PCNSL. Whether rituximab has any beneficial effect remains uncertain.

Primary and secondary central nervous system mature T- and NK-cell lymphomas

Primary central nervous system (CNS) mature T- and NK-cell lymphomas are rare, only comprising 2% to 3% of all primary CNS lymphomas. Among them, peripheral T-cell lymphoma, not otherwise specified, anaplastic large cell lymphoma (ALCL), and extranodal NK/T-cell lymphoma (ENKTL) are the commonly reported histological subtypes. Secondary CNS T-cell lymphoma generally affects about 5% of patients with T- or NK-cell lymphoma, with some exceptions. Acute and lymphomatous subtypes of adult T-cell leukemia/lymphoma (ATLL) have high risk of CNS progression, may affect up to 20% of patients; ALK-positive ALCL with extranodal involvement >1 also has high risk of CNS progression. However, the impact and the optimal methodology of CNS prophylaxis remain unclear in systemic T-cell lymphomas. There are little data on the treatment strategy of primary and secondary CNS T-cell lymphoma. Treatment strategy derived from B-cell CNS primary lymphoma is generally used; this includes induction therapy with high-dose methotrexate-based regimens, followed by high-dose chemotherapy with autologous stem cell transplant in fit patients. There are unmet needs for patients who are not fit for intensive chemotherapy. The prognosis after CNS progression in T-cell lymphoma is dismal with the median overall survival of less than 1 year. New agents targeting T-cell lymphomas are emerging and should be tested in patients with mature T- and NK-cell lymphoma who suffer from CNS involvement.

Primary central nervous system lymphoma: a narrative review of ongoing clinical trials and goals for future studies

Primary central nervous system lymphoma (PCNSL) is a rare disease of the brain, spine, cerebrospinal fluid (CSF) and/or vitreoretinal space. PCNSL is chemo and radiosensitive but relapse is common even years after initial treatment. Outside of consensus regarding the use of high-dose methotrexate (HD-MTX) for first line treatment, there is little uniformity in the management of newly diagnosed or relapsed PCNSL. The lack of consensus is driven by a paucity of randomized trials in this disease. Prospective studies are troubled by low enrollment, the lack of a standard induction regimen, and a varied approach to consolidation strategies. Moreover, the PCNSL patient population is heterogeneous and includes a high proportion of elderly or frail patients and consists of patients manifesting disease in varied compartments of the central nervous system (CNS). As a result, current treatment strategies vary widely and are often dictated by physician and institutional preference or regional practice. This review provides an overview of recently completed and ongoing therapeutic studies for patients with newly diagnosed and recurrent or refractory PCNSL. It discusses the existing evidence behind common approaches to induction and consolidation or maintenance regimens as well as the recent data regarding management of recurrent disease. Finally, it highlights the complexity of trial design in this disease and provides a framework for the design of future studies, which are needed to identify patient populations likely to benefit from specific induction, consolidation, or maintenance therapies.

Diagnosis, prognosis and treatment of primary central nervous system lymphoma in the elderly population (Review)

Primary central nervous system lymphoma (PCNSL) is a rare subtype of extranodal non-Hodgkin lymphoma that is unique and different from systemic diffuse large B-cell lymphomas. The median age at diagnosis of PCNSL is 65 years and its incidence is rising rapidly in the elderly population. A total of ≥20% of all patients with PCNSL are ≥80 years old. Notably, age has been identified as an independent poor prognostic factor for PCNSL. Elderly patients have an inferior prognosis to that of younger patients and are more severely affected by iatrogenic toxicity; therefore, elderly patients represent a unique and vulnerable treatment subgroup. The present review summarized the available literature to provide an improved understanding of the epidemiology, clinical characteristics, diagnosis, prognosis and management of PCNSL in the elderly population. Notably, the incidence of PCNSL in immunocompetent elderly patients, predominantly in men, is increasing. For the diagnosis of CNSL, imaging-guided stereotactic biopsy is considered the gold standard. When stereotactic biopsy is not possible or conclusive, certain biomarkers have been described that can help establish a diagnosis. PCNSL has a very poor prognosis in the elderly, even though several prognostic scoring systems exist and several prognostic markers have been reported in patients with PCNSL. Furthermore, the treatment of elderly patients remains challenging; it is unlikely that a novel agent could be used as a curative monotherapy; however, a combination of novel agents with polychemotherapy or its combination with other novel drugs may have therapeutic potential.

High-dose methotrexate-based regimens and post-remission consolidation for treatment of newly diagnosed primary CNS lymphoma: meta-analysis of clinical trials

With the exception of high-dose methotrexate (HD-MTX), there is currently no defined standard treatment for newly diagnosed primary central nervous system lymphoma (PCNSL). This review focused on first-line induction and consolidation treatment of PCNSL and aimed to determine the optimal combination of HD-MTX and the long-term beneficial consolidation methods. A comprehensive literature search of MEDLINE identified 1407 studies, among which 31 studies met the inclusion criteria. The meta-analysis was performed by using Stata SE version 15. Forest plots were generated to report combined outcomes like the complete response rate (CRR), overall survival, and progression-free survival. We also conducted univariate regression analyses of the baseline characteristics to identify the source of heterogeneity. Pooled analysis showed a CRR of 41% across all HD-MTX-based regimens, and three- and four-drug regimens had better CRRs than HD-MTX monotherapy. In all combinations based on HD-MTX, the HD-MTX + procarbazine + vincristine (MPV) regimen showed pooled CRRs of 63% and 58% with and without rituximab, respectively, followed by the rituximab + HD-MTX + temozolomide regimen, which showed a pooled CRR of 60%. Pooled PFS and OS showed that post-remission consolidation with autologous stem cell transplantation (ASCT) was associated with the best survival outcome, with a pooled 2-year OS of 80%, a 2-year PFS of 74%, a 5-year OS of 77%, and a 5-year PFS of 63%. Next, whole-brain radiation therapy (WBRT) + chemotherapy showed a pooled 2-year OS of 72%, 2-year PFS of 56%, 5-year OS of 55%, and 5-year PFS of 41%, with no detectable CR heterogeneity throughout the entire treatment process. In HD-MTX-based therapy of newly diagnosed PCNSL, MPV with or without rituximab can be chosen as the inductive regimen, and the rituximab + HD-MTX + temozolomide regimen is also a practical choice. Based on our study, high-dose chemotherapy supported by ASCT is an efficacious approach for consolidation. Consolidation with WBRT + chemotherapy can be another feasible approach.

Primary Central Nervous System Lymphoma: Evolving Biologic Insights and Recent Therapeutic Advances

Primary central nervous system lymphoma (PCNSL) is a rare and clinically aggressive disease entity associated with poor survival. Though high-dose methotrexate-based immunochemotherapy approaches are effective at inducing responses, few patients experience long-term durable remissions. Recently, novel insights into the biology of this unique disease have been elucidated and have paved the way for the investigation of rational approaches such as Bruton tyrosine kinase inhibition and immunomodulation. Although these strategies can induce high response rates in PCNSL, remissions are short lived, with median progression-free survivals in the range of 6 months or less. Moving forward, understanding the mechanisms of treatment resistance with these and other novel agents is key to developing optimal combinatorial strategies. New approaches such as immune checkpoint inhibition and chimeric antigen receptor T-cell therapy are under investigation for PCNSL and thus far demonstrate activity in anecdotal clinical experiences. Future trials should focus on investigating novel rational combinations designed to optimally target the biology of PCNSL and simultaneously investigate mechanisms of resistance leading to treatment failure.

Venous Thromboembolism Prophylaxis with Low-Molecular-Weight Heparin in Primary Central Nervous System Lymphoma

BACKGROUND

Venous thromboembolism (VTE) is a frequent, potentially lethal complication in individuals with cancer. Patients with brain tumors are at particularly high risk for VTE. Primary central nervous system lymphoma (PCNSL) is a rare subtype of diffuse large B cell lymphoma, involving the craniospinal axis. The incidence of VTE in patients with PCNSL was reported as very high, occurring mostly in the early period of therapy.

OBJECTIVES

We aimed to evaluate the efficacy and safety of prophylactic low-molecular-weight heparin (LMWH) throughout the treatment of PCNSL.

PATIENTS

All patients >18 years of age diagnosed and treated for PCNSL at our institution in 2005-2017 were included.

RESULTS

There were 44 patients; mean age at diagnosis was 61.5 years. Three patients (6.8%) had a personal history of thrombosis, 11 (25%) had a history of diabetes or smoking, and 32 (72%) had an Eastern Cooperative Oncology Group performance status of 0-1 at diagnosis. During treatment with LMWH, no VTE events were recorded; 2 (4.5%) patients experienced a minor bleeding event and 1 (2.3%) a major bleeding event.

CONCLUSIONS

Among our 44 patients with PCNSL treated with prophylactic LMWH, no VTE events were recorded, and only 1 (asymptomatic) intracranial bleed was recorded. Within the limitations of a retrospective nonrandomized study, our findings suggest that VTE prophylaxis may be beneficial for individuals with PCNSL.

Apparent diffusion coefficient as a valuable quantitative parameter for predicting clinical outcomes in patients with newly diagnosed primary CNS lymphoma

Background

This study attempted to identify novel prognostic factors in patients with newly diagnosed primary central nervous system lymphoma (PCNSL) using magnetic resonance imaging (MRI).

Methods

We retrospectively evaluated 67 patients diagnosed with central nervous system (CNS) tumors. The enrollment criteria were as follows: i) pathologic diagnosis of CNS lymphoma, ii) no evidence of systemic involvement, iii) no evidence of human immunodeficiency virus-1 infection or other immunodeficiencies, and iv) MRI scans available at diagnosis. Fifty-two patients met these criteria and were enrolled.

Results

The 3-year overall survival (OS) and failure-free survival rates were 69.7% and 45.6%, respectively, with a median follow-up duration of 36.2 months. OS of patients with low apparent diffusion coefficient (ADC) was lower than those with higher ADC. Multivariate analysis revealed that old age (>60 yr) [hazard ratio (HR), 20.372; P=0.001], Eastern Cooperative Oncology Group performance status (ECOG PS) ≥2 (HR, 10.429; P<0.001), higher lactate dehydrogenase (LDH) levels (HR, 7.408; P=0.001), and low ADC (HR, 0.273; P=0.009) were associated with lower OS. We modified the conventional prognostic scoring system using low ADC, old age (>60 yr), ECOG PS ≥2, and higher LDH. The risk of death was categorized as high (score 3-4), intermediate-2 (score 2), intermediate-1 (score 1), and low (score 0), with three-year OS rates of 33.5%, 55.4%, 88.9%, and 100%, respectively.

Conclusion

ADC demonstrated significant prognostic value for long-term survival in patients with newly diagnosed PCNSL. Low ADC was an independent unfavorable prognostic factor, suggesting that ADC obtained from MRI can improve the current prognostic scoring system.

The Role of Rituximab in Primary Central Nervous System Lymphoma

Purpose of Review

The treatment of primary central nervous system lymphoma (PCNSL) is still under debate. One of the issues is the role of rituximab in improving the outcome. Here, we summarize the existing evidence, and comment on the literature on this topic.

Recent Findings

Two randomized controlled studies have been published recently, with conflicting results. Although the evidence of the benefit of rituximab is limited, it is already incorporated into many treatment regimens, both in studies and in standard clinical practice.

Summary

The use of rituximab in PCNSL is still a matter of debate. A positive effect on the outcome is uncertain. However, there are no clinical signs of significantly increased toxicity. The uncertain positive effect should therefore be weighed against the increased costs of the treatment.

Advances and challenges in the treatment of primary central nervous system lymphoma

Primary central nervous system lymphoma (PCNSL), a rare variant of non-Hodgkin's lymphoma, is characterized by distinct biological characteristics and clinical behaviors, and patient prognosis is not satisfactory. The advent of high-dose (HD) methotrexate (HD-MTX) therapy has significantly improved PCNSL prognosis. Currently, HD-MTX-based chemotherapy regimens are recognized as first-line treatment. PCNSL is sensitive to radiotherapy, and whole-brain radiotherapy (WBRT) can consolidate response to chemotherapy; however, WBRT-associated delayed neurotoxicity leads to neurocognitive impairment, especially in elderly patients. Other effective approaches include rituximab, temozolomide, and autologous stem-cell transplantation (ASCT). In addition, new drugs against PCNSL such as those targeting the B-cell receptor signaling pathway, are undergoing clinical trials. However, optimal therapeutic approaches in PCNSL remain undefined. This review provides an overview of advances in surgical approaches, induction chemotherapy, radiotherapy, ASCT, salvage treatments, and novel therapeutic approaches in immunocompetent patients with PCNSL in the past 5 years. Additionally, therapeutic progress in elderly patients and in those with relapsed/refractory PCNSL is also summarized based on the outcomes of recent clinical studies.

Comprehensive approach to diagnosis and treatment of newly diagnosed primary CNS lymphoma

Primary central nervous system lymphoma (PCNSL) is a rare form of non-Hodgkin lymphoma that affects the brain parenchyma, spinal cord, eyes, and cerebrospinal fluid without evidence of systemic, non-CNS involvement. PCNSL is uncommon and only a few randomized trials have been completed in the first-line setting. Over the past decades, the prognosis of PCNSL has improved, mainly due to the introduction and widespread use of high-dose methotrexate, which is now the backbone of all first-line treatment polychemotherapy regimens. Despite this progress, durable remission is recorded in only 50% of patients, and therapy can be associated with significant late neurotoxicity. Here, we overview the epidemiology, clinical presentation, staging evaluation, prognosis, and current up-to-date treatment of immunocompetent PCNSL patients.

Serum levels of soluble programmed death-ligand 1 (sPD-L1) in patients with primary central nervous system diffuse large B-cell lymphoma

Background

The interaction of programmed death-1 protein (PD-1) and programmed death-1 ligand (PD-L1) produces immunosuppressive activity, protecting tumor cells from anti-tumor immunity and possibly releasing soluble PD-L1 (sPD-L1) from PD-L1 expressing tumor cells. Therefore, we measured serum levels of sPD-L1 in patients with primary central nervous system lymphoma (PCNSL) and explored its clinical implications.

Methods

Sixty-eight patients with newly diagnosed PCNSL had diffuse large B-cell lymphoma and were treated with high-dose methotrexate-containing chemotherapy. The measurement of sPD-L1 and cytokines was performed using serum samples archived at diagnosis, and the tissue expression of PD-L1 was also analyzed from archived paraffin-embedded tissue blocks. Disease relapse, progression-free survival (PFS), and overall survival (OS) were analyzed according to the extent of sPD-L1 in serum and PD-L1 in tissue.

Results

The median level of serum sPD-L1 (0.429 ng/mL) was higher than in healthy control patients (0.364 ng/mL). The occurrence of relapse was more frequent in the high sPD-L1 (78%) than the low sPD-L1 group (50%), though the groups did not have different clinical or pathological characteristics at diagnosis. As a result, the OS and PFS for the high sPD-L1 group were significantly lower than those in the low group. PD-L1-positive tumor cells were found in 35 patients (67%), and the extent of PD-L1-postive tumor cells was positively associated with serum sPD-L1 levels (r = 0.299, P = 0.031). Among the 34 cytokines analyzed, only the serum level of IL-7 correlated with the serum level of sPD-L1 (r = 0.521, P < 0.001).

Conclusions

Serum levels of sPD-L1 could reflect the expression of PD-L1 in PCNSL tumor cells and predict patient survival outcomes. Therefore, sPD-L1 in serum could be a feasible biomarker for determining a risk-adapted treatment strategy for PCNSL patients.

Trial registration

The study population was patients who were diagnosed with PCNSL between January 2009 and February 2017 and registered for our prospective cohort studies after providing written informed consent (ClinicalTrials.gov: NCT00822731 [date of registration - January 14, 2009] and NCT01877109 [date of registration - June 13, 2013]).

Eye involvement in primary central nervous system lymphoma

Primary central nervous system lymphoma (PCNSL) may manifest initially in the eye (termed vitreoretinal lymphoma or VRL) or in non-ocular CNS compartments, or in both. The nature of the onset of PCNSL implies two clinical specialists - ophthalmologists and neuro-oncologists - independently may assess the primary presentation of this rare malignancy. Clinically relevant perspectives on expectations of PCNSL manifestation in both ocular and non-ocular CNS compartments would help inform management practices in each specialty, which should impact clinical outcomes. A recent increase in the number of published PCNSL cohort studies provides new opportunity to review the current prevalence rates of ocular involvement, and the timing of this involvement over the course of disease. In PCNSL cohorts defined by non-ocular CNS compartment involvement, with or without ocular involvement (termed "PCNSL ± ocular involvement" cohorts), mean rates of concomitant VRL at diagnosis, or at any time during the course, are 10% and 16%, respectively. Only a few individuals within this cohort group present with exclusive eye disease (<5%), and the rate of secondary ocular involvement is only 5-9%. In PCNSL cohorts defined by the involvement of the ocular compartment, with or without non-ocular CNS involvement (termed "VRL ± non-ocular CNS involvement" cohorts), 58% of persons have a primary ocular diagnosis, which carries a 50% risk of secondary involvement in the CNS beyond the eye. Rates of non-ocular CNS involvement with VRL at diagnosis or over the course of disease are 41% and 69%, respectively.

Risk Prediction for Early Mortality in Patients with Newly Diagnosed Primary CNS Lymphoma

Background: Overall survival of patients with primary CNS lymphoma (PCNSL) has improved since the introduction of immunochemotherapy. However, up to 10-15% of PCNSL patients still die shortly after diagnosis. In the present study, we aimed to investigate the risk factors of early mortality (death within 60 days after diagnosis) in patients with PCNSL.

Methods: We included newly diagnosed PCNSL patients in a tertiary medical center in Taiwan between January 1, 2002 and May 31, 2018. Clinical risk factors were collected and compared between PCNSL patients who had and did not have early mortality.

Results: A total of 133 consecutive patients with PCNSL were included in this study. Approximately 9.8% of the PCNSL patients had early mortality. In multivariate analysis, age ≥ 80 (adjusted hazard ratio [HR] 3.34, 95% confidence interval [CI] 1.01-11.04, p = 0.048) and involvement of the basal ganglia (adjusted HR 4.85, 95% CI 1.47-15.95, p = 0.009) were identified as independent risk factors of early mortality. Use of MTX-based chemotherapy served as an independent protective factor for early mortality (adjusted HR 0.19, 95% CI 0.05-0.67, p = 0.010). Infection and tumor-associated mass effect contributed most to early mortality.

Conclusion: Early mortality is not uncommon in patients with PCNSL. Identification of patients with higher risk may help clinicians with initiating appropriate surveillance and management.

HDMTX-based induction therapy followed by consolidation with conventional systemic chemotherapy and intraventricular therapy (modified Bonn protocol) in primary CNS lymphoma: a monocentric retrospective analysis

Background

To evaluate outcome and toxicity of High-dose methotrexate (HDMTX)-based induction therapy followed by consolidation with conventional systemic chemotherapy and facultative intraventricular therapy (modified Bonn protocol) in patients with primary CNS lymphoma (PCNSL).

Methods

Between 01/2005 and 12/2013 113 patients with newly diagnosed PCNSL presented at our center; 98 of those qualified for HDMTX based chemotherapy, received a modified Bonn protocol and were included in the analysis. The treatment regimen was based on the “Bonn protocol”, but modified by omission of systemic drugs not able to cross the intact blood brain barrier. Intraventricular therapy was postponed until completion of three induction chemotherapy cycles or was replaced by intrathecal liposomal AraC and rituximab was added to induction from 2010 onwards.

Results

Median patient age was 67 years (range 38–83). Complete response/complete response unconfirmed (CR/CRu) was achieved in 59/98 patients (60%), partial response (PR) in 9/98 patients (9%). Twenty-four patients (23%) had progressive disease (PD), 6 (6%) died on therapy. Median progression-free survival (PFS) for all patients was 11.4 months, median overall survival (OS) 29.1 months. A trend to better outcome for intraventricular therapy versus intrathecal liposomal AraC was found in patients < 65 years (HR 0.53 [0.19–1.47] for OS and 0.46 [0.21–1.02] for PFS. Ommaya reservoir infection occurred in 3/33 patients (9%).

Conclusions

The data of this single center experience suggest that the outcome with a modified Bonn protocol was comparable to that of the previous regimen, showed fewer Ommaya reservoir infections and may have a trend for better outcome with intraventricular therapy.

Electronic supplementary material

The online version of this article (10.1186/s42466-019-0024-2) contains supplementary material, which is available to authorized users.

Is whole-brain radiotherapy still a standard treatment for primary central nervous system lymphomas?

PURPOSE OF REVIEW

In primary central nervous system lymphomas (PCNSL), optimal therapy remains to be established, and the role of whole-brain radiotherapy (WBRT) is a matter of debate. With radiation alone, transient responses and clinical improvement are frequent, but long-term disease control is exceptional. WBRT has been considered possible consolidation therapy after high-dose methotrexate (HDMTX)-based initial chemotherapy. This strategy has been questioned due to a high risk of delayed neurotoxicity after combined treatment. This review analyses the current role of WBRT in PCNSL.

RECENT FINDINGS

Neither in retrospective analyses nor in randomized trials, an overall survival benefit with WBRT in addition to HDMTX-based initial chemotherapy could be found. On the other hand, a recent randomized trial did not show superiority of consolidation with high-dose chemotherapy followed by autologous stem-cell transplantation to consolidation WBRT after initial HDMTX-based polychemotherapy. This finding, however, is probably due to an intense initial therapy and to a small number of patients having reached consolidation and randomization to WBRT vs. high-dose chemotherapy followed by autologous stem-cell transplantation.

SUMMARY

The current role of WBRT in PCNSL is confined to patients who cannot tolerate chemotherapy or have failed it. WBRT should not routinely be used for consolidation of HDMTX-based chemotherapy due to lack of evidence of efficacy as additional treatment and due to a high risk of neurotoxicity.

Radiotherapy or Autologous Stem-Cell Transplantation for Primary CNS Lymphoma in Patients 60 Years of Age and Younger: Results of the Intergroup ANOCEF-GOELAMS Randomized Phase II PRECIS Study

PURPOSE

To determine the efficacy and toxicity of chemoimmunotherapy followed by either whole-brain radiotherapy (WBRT) or intensive chemotherapy and autologous stem-cell transplantation (ASCT) as a first-line treatment of primary CNS lymphoma (PCNSL).

PATIENTS AND METHODS

Immunocompetent patients (18 to 60 years of age) with untreated PCNSL were randomly assigned to receive WBRT or ASCT as consolidation treatment after induction chemotherapy consisting of two cycles of R-MBVP (rituximab 375 mg/m2 day (D) 1, methotrexate 3 g/m2 D1; D15, VP16 100 mg/m2 D2, BCNU 100 mg/m2 D3, prednisone 60 mg/kg/d D1-D5) followed by two cycles of R-AraC (rituximab 375 mg/m2 D1, cytarabine 3 g/m2 D1 to D2). Intensive chemotherapy consisted of thiotepa (250 mg/m2/d D9; D8; D7), busulfan (8 mg/kg D6 through D4), and cyclophosphamide (60 mg/kg/d D3; D2). WBRT delivered 40 Gy (2 Gy/fraction). The primary end point was 2-year progression-free survival. Cognitive outcome was the main secondary end point. Analysis was intention to treat in a noncomparative phase II trial.

RESULTS

Between October 2008 and February 2014, 140 patients were recruited from 23 French centers. Both WBRT and ASCT met the predetermined threshold (among the first 38 patients in each group, at least 24 patients were alive and disease free at 2 years). The 2-year progression-free survival rates were 63% (95% CI, 49% to 81%) and 87% (95% CI, 77% to 98%) in the WBRT and ASCT arms, respectively. Toxicity deaths were recorded in one and five patients after WBRT and ASCT, respectively. Cognitive impairment was observed after WBRT, whereas cognitive functions were preserved or improved after ASCT.

CONCLUSION

WBRT and ASCT are effective consolidation treatments for patients with PCNSL who are 60 years of age and younger. The efficacy end points tended to favor the ASCT arm. The specific risk of each procedure should be considered.

Recurrent Epstein-Barr Virus-positive (EBV+) Primary Central Nervous System Lymphoma (PCNSL) in a Patient with Clinical Features of Chronic Lymphocytic Inflammation with Pontine Perivascular Enhancement Responsive to Steroids (CLIPPERS)

Primary central nervous system lymphoma (PCNSL) and chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) can share clinical features and may be indistinguishable, even after brain biopsy. We encountered a case of Epstein-Barr virus-positive (EBV+) PCNSL recurrence in a patient with clinical features of CLIPPERS, and repeat brain biopsy was required to reach the correct diagnosis. Four years after the initial diagnosis and treatment of PCNSL, "peppering" punctate enhanced lesions with transient steroid responsiveness were detected during brain magnetic resonance imaging (MRI). A second brain biopsy supported a diagnosis of CLIPPERS, while a third biopsy confirmed the diagnosis of recurrent PCNSL.

Rituximab in patients with primary CNS lymphoma (HOVON 105/ALLG NHL 24): a randomised, open-label, phase 3 intergroup study

BACKGROUND

The prognosis for primary CNS lymphoma has improved with the use of high-dose methotrexate-based chemotherapy, but patient outcomes remain poor. Rituximab, a chimeric monoclonal antibody that targets the CD20 cell surface protein, has substantial activity in systemic CD20-positive diffuse large B-cell lymphoma, but its efficacy in primary CNS lymphoma is unknown and low penetration of the large rituximab molecule through the blood-brain barrier could limit its effect. We aimed to investigate the addition of rituximab to a high-dose methotrexate-based chemotherapy regimen in patients with newly diagnosed primary CNS lymphoma.

METHODS

This intergroup, multicentre, open-label, randomised phase 3 study was done at 23 hospitals in the Netherlands, Australia, and New Zealand. Non-immunocompromised patients aged 18-70 years with newly diagnosed primary CNS lymphoma were randomly assigned (1:1) to receive methotrexate-based chemotherapy with or without intravenous rituximab. We used a web-based randomisation system with stratification by centre, age, and Eastern Cooperative Oncology Group-WHO performance status, and a minimisation procedure. All group assignment was open label and neither investigators nor patients were masked to allocation. All patients were treated with two 28-day cycles of induction chemotherapy, consisting of intravenous methotrexate 3 g per m² on days 1 and 15, intravenous carmustine 100 mg per m² on day 4, intravenous teniposide 100 mg per m² on days 2 and 3, and oral prednisone 60 mg per m² on days 1-5, with (R-MBVP) or without (MBVP) intravenous rituximab 375 mg per m² on days 0, 7, 14, and 21 in cycle one and days 0 and 14 in cycle two. Patients with response at the end of induction subsequently received high-dose cytarabine and, in patients aged 60 years or younger, low-dose whole-brain radiotherapy. The primary endpoint was event-free survival, with events defined as not reaching complete response or complete response unconfirmed at the end of treatment, or progression or death after response; analysis was adjusted for age and performance score. Patients were analysed on a modified intention-to-treat basis. This trial is registered with the Nederlands Trial Register, number NTR2427, and the Australian New Zealand Clinical Trials Registry, number ACTRN12610000908033. The trial was closed on May 27, 2016, after achieving complete accrual, and follow-up is ongoing.

FINDINGS

Between Aug 3, 2010, and May 27, 2016, we recruited 200 patients (109 men and 91 women; median age was 61 years [IQR 55-67]). We randomly assigned 100 patients to MBVP and 99 patients to R-MBVP. One patient was randomly assigned to the R-MBVP group but found to be ineligible because of an incorrect diagnosis and was excluded from all analyses. After a median follow-up of 32·9 months (IQR 23·9-51·5), 98 patients had had an event (51 in the MBVP group and 47 in the R-MBVP group), of whom 79 had died (41 in the MBVP group and 38 in the R-MBVP group). Event-free survival at 1 year was 49% (95% CI 39-58) in the MBVP group (no rituximab) and 52% (42-61) in the R-MBVP group (with rituximab; hazard ratio 1·00, 95% CI 0·70-1·43, p=0·99). Grade 3 or 4 adverse events occurred in 58 (58%) patients in the MBVP group and 63 (64%) patients in the R-MBVP group, with infections (24 [24%] patients receiving MBVP vs 21 [21%] patients receiving R-MBVP), haematological toxicity (15 [15%] vs 12 [12%]), and nervous system disorders (ten [10%] vs 15 [15%]) being the most common. Life-threatening or fatal serious adverse events occurred in 12 (12%) patients in the MBVP group and ten (10%) patients in the R-MBVP group, and five (5%) patients in the MBVP group and three (3%) in the R-MBVP group died from treatment-related causes.

INTERPRETATION

We found no clear benefit of addition of rituximab to methotrexate, carmustine, teniposide, and prednisone chemotherapy in primary CNS lymphoma. Therefore, the results of this study do not support the use of rituximab as a component of standard treatment in primary CNS lymphoma.

FUNDING

Roche, the Dutch Cancer Society, and Stichting STOPhersentumoren.

Management of primary central nervous system lymphoma

A rare tumor, primary central nervous system lymphoma can affect immunocompetent and immunocompromised patients. While sensitive to radiotherapy or chemotherapy crossing the blood-brain barrier, it often recurs. Modern treatment consists of high-dose methotrexate-based induction chemotherapy, often followed by consolidation with either radiotherapy or further chemotherapy. Neurotoxicity is however a concern with radiotherapy, especially for patients older than 60 years. The benefit of the addition of rituximab to chemotherapy is unclear. Targeted therapies and immunotherapy have been effective in some patients and are tested on a larger scale. Survival has improved in the last decade, but remains poor in older patients.