The prevention of central nervous system relapse in diffuse large B-cell lymphoma: a British Society for Haematology good practice paper

Biological Findings and Clinical Outcomes in Patients Treated With R-CHOP Plus High-Dose Methotrexate as First-Line Therapy in Large B-Cell Lymphoma With Testis Involvement

Primary testicular lymphoma (PTL) is a rare occurrence of diffuse large B-cell lymphoma (DLBCL) that accounts for 1%-2% of all cases. Nodal DLBCL with testis involvement (DLBCL-T) and PTL are associated with poor prognosis, with high incidence of central nervous system relapse. Fifteen patients (median age 60 years) with PTL (n = 5) or DLBCL-T (n = 10) received high-dose methotrexate + R-CHOP. Overall, complete response (CR) rate was 73% and overall response rate 86%. With a 3.9-year median follow-up, 100% of patients with PTL had CR and none relapsed. On the contrary, 55% of DLBCL-T patients achieved CR among which only one was still in remission at the end of follow-up. Molecular parallels between PTL and Primary CNS Lymphoma (PCNSL) suggest shared origins, urging further research for tailored treatments and enhanced understanding of these lymphomas' biology.

CNS prophylaxis in large B-cell lymphomas: A balance with three pans

Given the significant limitations of available literature, central nervous system (CNS) prophylaxis in large B-cell lymphomas remains debatable. Wilson and colleagues provide cautious recommendations, on a case-by-case basis, useful to guide discussion with individual patient. In daily practice, CNS relapse risk, prophylaxis safety and prognosis of CNS recurrence must be considered. Commentary on: Wilson et al. Central nervous system prophylaxis in large B-cell lymphoma: A British Society for Haematology Good Practice Paper. Br J Haematol 2024; 205:2198-2205.

Central nervous system prophylaxis in large B-cell lymphoma: A British Society for Haematology Good Practice Paper

This Good Practice Paper provides recommendations for the baseline investigation, risk stratification and use of prophylactic interventions for patients with large B-cell lymphoma at risk of central nervous system relapse. Recent evidence which has questioned the role of high-dose methotrexate in this clinical scenario is discussed in detail.

Cerebrospinal fluid IL-6 and IL-10 as promising diagnostic and therapeutic prognostic biomarkers for secondary central nervous system lymphoma

BACKGROUND

Accurate diagnosis and therapeutic response to secondary central nervous system lymphoma (SCNSL) are challenges that need to be addressed. We assessed the value of cerebrospinal fluid (CSF) cytokine levels for diagnosis and post-therapeutic prognosis in patients with SCNSL.

METHODS

This retrospective study included 234 patients with non-Hodgkin lymphoma (NHL), including the SCNSL group (n = 57) and the non-SCNSL group (n = 177). The Mann-Whitney U test was used to compare the cytokine profiles between SCNSL and non-SCNSL group. Receiver operating characteristic curve was used to determine the diagnostic ability of CSF cytokine levels for SCNSL. The predictive value of CSF cytokine concentrations for progression free survival of patients with SCNSL was evaluated using a log-rank test.

RESULTS

CSF IL-6 and IL-10 levels in SCNSL group were significantly elevated compared with those in the other two groups. ROC curve showed that the cutoff values of IL-6 and IL-10 in CSF were 10.13 pg/ml and 7.82pg/ml, which yielded the diagnostic sensitivity were 62.34% and 76.23%, specificity were 87.57% and 88.31%, respectively. Furthermore, combining CSF IL-6 and IL-10 levels significantly improved the diagnostic efficacy. CSF IL-6 and IL-10 levels in SCNSL patients in complete remission under chemotherapy were significantly reduced. In addition, poor progression free survival (PFS) in patients with SCNSL was related to increased CSF IL-10 levels at diagnosis, but not with increased CSF IL-6 levels.

CONCLUSION

CSF IL-6 and IL-10 levels are promising biomarkers for diagnosis and predictors of response for SCNSL.

Central nervous system lymphomas-Assessment and treatment and prevention of central nervous system relapse

In this review focused on lymphoma and the central nervous system (CNS), we summarize recent developments in the management of primary (PCNSL) and secondary CNS lymphoma (SCNSL), treatment of CNS lymphoma in the older population, the neuroradiological assessment of CNS lymphoma and finally highlight the ongoing debate on optimal CNS prophylaxis. The section on PCNSL focuses on the different approaches available for frontline treatment in Europe and the United States and discusses consolidation strategies. We then highlight available strategies to treat PCNSL in the elderly population, an area of unmet need. New therapies aiming at minimizing toxicity and prioritizing quality of life are emerging for these patients. Secondary CNS lymphoma, especially in the relapsed/refractory setting is another area of unmet need, and the efficacy of CAR-T cell therapy is being explored. We provide an overview of the imaging challenges in the neuroradiological assessment of CNS lymphoma. Finally, the section on CNS prophylaxis summarizes recent findings from large retrospective studies challenging the efficacy of present approaches to prophylaxis in higher-risk patients with lymphoma.

A European consensus recommendation on the management of delayed methotrexate elimination: supportive measures, leucovorin rescue and glucarpidase treatment

High-dose methotrexate (HDMTX) is used in the treatment of a range of adult and childhood cancers. Although HDMTX can provide effective anti-tumor activity with an acceptable safety profile for most patients, delayed methotrexate elimination (DME) develops in a minority of patients receiving HDMTX and may be accompanied by renal dysfunction and potentially life-threatening toxicity. A panel of European physicians with experience in the use of HDMTX as well as of glucarpidase convened to develop a series of consensus statements to provide practical guidance on the prevention and treatment of DME, including the use of glucarpidase. Robust implementation of supportive measures including hyperhydration and urine alkalinization emerged as critical in order to reduce the risk of DME with HDMTX treatment, with leucovorin rescue critical in reducing the risk of DME complications. Early recognition of DME is important to promptly implement appropriate treatment including, intensified hydration, high-dose leucovorin and, when appropriate, glucarpidase.

CNS prophylaxis is (mostly) futile in DLBCL

Central nervous system (CNS) relapse of diffuse large B-cell lymphoma (DLBCL) is associated with a poor prognosis, with a median overall survival of approximately five months [1]. The risk for CNS disease has been estimated to be about 5% overall [2], but it is significantly higher in certain high-risk groups [3]. CNS prophylaxis is often administered to patients felt to be at high risk for CNS recurrence. Options for CNS prophylaxis include high-dose methotrexate (HD-MTX) and intrathecal (IT) chemotherapy with methotrexate and/or cytarabine. However, a number of recent retrospective analyses have called into question the efficacy of prophylaxis. Here, we aim to review the literature regarding CNS prophylaxis with HD-MTX or IT chemotherapy in DLBCL. Our review and discussion exclude Burkitt lymphoma and lymphoblastic leukemia/lymphoma, for which standard treatment protocols include CNS prophylaxis. We also exclude double and triple hit lymphoma (DHL, THL) as it is generally accepted that these patients are at a high risk of CNS relapse. Based on the results of several recent studies, we recommend consideration of IT chemotherapy instead of HD-MTX if prophylaxis is desired due to better tolerability. If HD-MTX is desired, it should be done after systemic therapy is completed to avoid treatment delays. We provide an algorithm to guide decision making. However, our review of the literature suggests that CNS prophylaxis by either means has no clear benefit.

Efficacy of intravenous high-dose methotrexate in preventing relapse to the central nervous system in R-CHOP(-like)-treated, high-risk, diffuse large B-cell lymphoma patients and its effect on mortality: a systematic review and meta-analysis

Central nervous system (CNS) relapse in patients with diffuse large B-cell lymphoma (DLBCL) carries a dismal prognosis and most clinical guidelines recommend CNS prophylaxis to patients deemed at high risk of CNS relapse. However, results from observational studies investigating the effect of CNS prophylaxis have yielded conflicting results. The aims of this study were to evaluate: (i) whether addition of prophylactic intravenous high-dose methotrexate (HD-MTX) reduces the risk of CNS relapse in high-risk DLBCL patients treated with R-CHOP or similar, and (ii) whether HD-MTX prophylaxis confers an overall survival benefit, irrespective of CNS relapse. We performed a systematic search of MEDLINE/PubMed and EMBASE for data on DLBCL patients at high risk of CNS relapse treated with R-CHOP or similar who received HD-MTX as an intervention and a comparator arm of patients who did not receive prophylaxis and/or intrathecal prophylaxis. A risk of bias was estimated using the ROBINS-I tool and the quality of the evidence was assessed by the GRADE approach. Finally, a meta- analysis based on the systematic review was conducted. A total of 1,812 studies were screened. No randomized controlled trials were identified. Seven observational studies comprising 1,661 patients met the inclusion criteria. We found a statistically non-significant relative risk of 0.54 (95% confidence interval: 0.27-1.07) of CNS relapse for patients receiving HD-MTX versus controls. The meta-analysis investigating mortality demonstrated a relative risk of death of 0.70 (95% confidence interval: 0.44-1.11) for patients treated with HD-MTX versus controls. The overall risk of bias was adjudged as "serious" and the quality of the evidence was rated as "low". In conclusion, our data indicate that HD-MTX does not prevent or, at best, only slightly reduces the risk of CNS relapse and confers no survival benefit.

Relapsed isolated CNS lymphoma treated with radiotherapy and intrathecal methotrexate followed by high-dose intravenous methotrexate, rituximab, and temozolomide: A case report

Key Clinical Message

Optimized treatments for relapsed isolated CNS lymphoma (RI-SCNSL) remains under investigation. Temozolomide combination-based therapy, which is often used in glioblastoma may be used as potential treatment in RI-SCNSL.

Abstract

One of the most common types of non-Hodgkin lymphoma (NHL) is diffuse large B-cell lymphoma (DLBCL). Despite advances in treatment, relapsed isolated CNS lymphoma (RI-SCNSL) from DLBCL remains an issue. The optimal approach in RI-SCNSL remains an area of active investigation as currently there is no high level of evidence for the treatments due to lack of randomized studies. In this case report, we present a DLBCL patient with CNS recurrence treated radiotherapy and intrathecal methotrexate (MTX) followed by intravenous high-dose MTX, rituximab, and temozolomide. To the best of our knowledge, this is the first case report describing RI-SCNSL treated with the regiments above which also include temozolomide which is used for glioblastoma.

Plasmablastic Lymphoma. A State-of-the-Art Review: Part 2-Focus on Therapy

The objective of this two-part review is to present a current and comprehensive understanding of the diagnosis and management of plasmablastic lymphoma. The first part, which was published previously, focused on the study of epidemiology, etiology, clinicopathological characteristics, differential diagnosis, prognostic variables, and the impact of plasmablastic lymphoma on specific populations. This second part addresses the difficult topic of the treatment of plasmablastic lymphoma, specifically examining both the conventional, consolidated approach and the novel therapeutic strategy.

Comparison of standardized prophylactic high-dose and intrathecal methotrexate for DLBCL with a high risk of CNS relapse

The efficacy of high-dose methotrexate (HD-MTX) for central nervous system (CNS) relapse prophylaxis in patients with high-risk diffuse large B-cell lymphoma (DLBCL) is controversial. We compared the prophylactic effects of HD-MTX and intrathecal methotrexate (IT-MTX) on CNS relapse in high-risk DLBCL, in a multicenter retrospective study. A total of 132 patients with DLBCL at high risk of CNS relapse who received frontline chemotherapy and IT-MTX from 2003 to 2013 (n = 34) or HD-MTX from 2014 to 2020 (n = 98) were included. After a median follow-up of 52 months (range: 9-174), 11 patients had isolated CNS relapse: six (6.1%) in the HD-MTX group and five (14.7%) in the IT-MTX group. The median time until CNS relapse was 38 months (range: 11-122), and the cumulative incidence of CNS relapse at 3 years was 3.9% in the HD-MTX group and 6.1% in the IT-MTX group (P = 0.93). Similar results were obtained after adjusting for background factors using propensity score-matched analysis (4.5% HD-MTX vs. 7.6% IT-MTX, P = 0.84). The CNS relapse rate in HD-MTX-treated patients was equivalent to that in IT-MTX patients, demonstrating that HD-MTX was not superior to IT-MTX in preventing CNS relapse.

Recent updates on central nervous system prophylaxis in patients with high-risk diffuse large B-cell lymphoma

The use of central nervous system (CNS) prophylaxis for patients with diffuse large B-cell lymphoma (DLBCL) remains controversial. Although uncommon, CNS relapses are invariably fatal in this otherwise curable disease. Accurate identification of patients at risk and the optimal approach to CNS prophylaxis therefore remains an area of unmet need. The existing literature, largely retrospective in nature, provides mixed conclusions regarding the efficacy of CNS prophylaxis. The utility of CNS prophylaxis has itself been challenged. In this review, we dissect the issues which render the value of CNS prophylaxis uncertain. We first compare international clinical guidelines for CNS prophylaxis. We then interrogate the factors that should be used to identify high-risk patients accurately. We also explore how clinical patterns of CNS relapse have changed in the pre-rituximab and rituximab era. We then discuss the efficacy of CNS-directed approaches, intensification of systemic treatment and other novel approaches in CNS prophylaxis. Improved diagnostics for early detection of CNS relapses and newer therapeutics for CNS prophylaxis are areas of active investigation. In an area where prospective, randomized studies are impracticable and lacking, guidance for the use of CNS prophylaxis will depend on rigorous statistical review of retrospective data.

High-Dose Methotrexate as CNS Prophylaxis in High-Risk Aggressive B-Cell Lymphoma

PURPOSE

CNS progression or relapse is an uncommon but devastating complication of aggressive B-cell lymphoma. There is no consensus regarding the optimal approach to CNS prophylaxis. This study was designed to determine whether high-dose methotrexate (HD-MTX) is effective at preventing CNS progression in patients at high risk of this complication.

PATIENTS AND METHODS

Patients age 18-80 years with aggressive B-cell lymphoma and high risk of CNS progression, treated with curative-intent anti-CD20-based chemoimmunotherapy, were included in this international, retrospective, observational study. Cause-specific hazard ratios (HRs) and cumulative risks of CNS progression were calculated according to use of HD-MTX, with time to CNS progression calculated from diagnosis for all patients (all-pts) and from completion of frontline systemic lymphoma induction therapy, for patients in complete response at completion of chemoimmunotherapy (CR-pts).

RESULTS

Two thousand four hundred eighteen all-pts (HD-MTX; n = 425) and 1,616 CR-pts (HD-MTX; n = 356) were included. CNS International Prognostic Index was 4-6 in 83.4% all-pts. Patients treated with HD-MTX had a lower risk of CNS progression (adjusted HR, 0.59 [95% CI, 0.38 to 0.90]; P = .014), but significance was not retained when confined to CR-pts (adjusted HR, 0.74 [95% CI, 0.42 to 1.30]; P = .29), with 5-year adjusted risk difference of 1.6% (95% CI, -1.5 to 4.4; all-pts) and 1.4% (95% CI, -1.5 to 4.1; CR-pts). Subgroups were underpowered to draw definitive conclusions regarding the efficacy of HD-MTX in individual high-risk clinical scenarios; however, there was no clear reduction in CNS progression risk with HD-MTX in any high-risk subgroup.

CONCLUSION

In this large study, high-risk patients receiving HD-MTX had a 7.2% 2-year risk of CNS progression, consistent with the progression risk in previously reported high-risk cohorts. Use of HD-MTX was not associated with a clinically meaningful reduction in risk of CNS progression.

Controversies in central nervous system prophylaxis of high-risk diffuse large B-cell lymphoma

PURPOSE OF REVIEW

Central nervous system (CNS) relapse in patients with diffuse large B-cell lymphoma (DLBCL) is an uncommon but devastating complication with an overall survival of less than 6 months. This article will review the recent updates on CNS prophylaxis including new potential advances in the identification of high-risk patients.

RECENT FINDINGS

The identification of patients at a high risk of CNS relapse is based on clinical and biological features has improved over recent years; however, the of different CNS prophylaxis strategies including intrathecal chemotherapy and high-dose methotrexate have been recently questioned in several large retrospective studies. The analysis of cell-free circulating tumor DNA (ctDNA) in the cerebrospinal fluid has been shown to identify patients with a high risk of CNS involvement and work is ongoing to identify how this can be used as a prognostic biomarker.

SUMMARY

Recent clinical retrospective data have questioned the effectiveness of intrathecal and high-dose methotrexate in the prevention of CNS relapse in high-risk DLBCL patients. The role of more sensitive methods to detect CNS involvement and the benefit of novel therapies in CNS relapse prevention are currently under evaluation.

CNS prophylaxis in aggressive B-cell lymphoma

The prevention of central nervous system (CNS) relapse in diffuse large B-cell lymphoma (DLBCL) continues to be one of the most contentious areas of lymphoma management. Outcomes for patients with secondary CNS lymphoma (SCNSL) have historically been very poor. However, in recent years improved responses have been reported with intensive immunochemotherapy approaches, and there is a growing interest in potential novel/cellular therapies. Traditional methods for selecting patients for CNS prophylaxis, including the CNS International Prognostic Index, are hampered by a lack of specificity, and there is accumulating evidence to question the efficacy of widely employed prophylactic interventions, including intrathecal and high-dose methotrexate (HD-MTX). Given the potential toxicity of HD-MTX in particular and the ongoing need to prioritize systemic disease control in high-risk patients, there is an urgent need to develop more robust methods for identifying patients at highest risk of CNS relapse, as well as investigating prophylactic interventions with greater efficacy. Here we review new evidence in this field from the last 5 years, focusing on the potential use of molecular diagnostics to improve the identification of high-risk patients, recent large data sets questioning the efficacy of HD-MTX, and the current approach to management of patients with SCNSL. We provide a suggested algorithm for approaching this very challenging clinical scenario.

SOHO State of the Art Updates and Next Questions: Prophylaxis and Management of Secondary CNS Lymphoma

Secondary CNS lymphoma (SCNSL) is a rare but frequently fatal complication of systemic lymphoma. There is no standard treatment for SCNSL, and patients who develop SCNSL at diagnosis or after frontline therapy often receive highly intensive chemotherapy regimens that are inactive against primary chemorefractory disease and too toxic for older, frail patients to tolerate. Because the prognosis of SCNSL is so poor, management has historically emphasized prevention, but the current methods of CNS prophylaxis are not universally effective. To improve both the prevention and management of SCNSL, better characterization of the molecular determinants of CNS invasion is needed. Novel treatments that are currently being studied in SCNSL include targeted pathway inhibitors and cellular therapy, but SCNSL patients are often excluded from clinical trials of promising new therapies.

Renal involvement of lymphomas proven by kidney biopsy: report of 10 cases from a tertiary care center and comparison with the literature

Lymphomas localized in the kidney are a rare entity that may be challenging to diagnose. We analyzed data from 10 patients with renal involvement of lymphoma diagnosed between 2009 and 2019 on fine needle biopsy from our tertiary center, and compared these with findings of 160 cases reported in the literature. Diffuse large B-cell lymphoma was the main histology subtype (40 and 38% in our sample and in the literature, respectively), followed by low-grade B-cell lymphomas, mostly from the marginal zone (MZ). Altogether, 106 patients had urological inaugural symptoms and 64 had general symptoms. Patients with urological presentation more often had renal masses than diffuse infiltration (p < 0.001), unilateral tumors (p = 0.0036) and low-grade B-cell lymphomas (17 vs 6%, p = 0.043). In both groups, nearly one-fourth of patients had diffuse (stage IV) lymphomas. Overall survival did not differ by the presence of urological/systemic symptoms, stage or aggressive lymphoma status. Notably, 3 of 10 patients from our series had MZ lymphomas associated with primary Sjögren syndrome revealed by acute kidney injury, including one where the autoimmune disease was detected. Lymphoproliferative disorders localized in the kidney are a challenging condition that can lead to detection of aggressive or diffuse lymphomas.

Predictive impact of soluble interleukin-2 receptor and number of extranodal sites for identification of patients at very high risk of CNS relapse in diffuse large B-cell lymphoma

There remains an unmet clinical need to identify which patients with diffuse large B-cell lymphoma (DLBCL) would benefit from central nervous system (CNS) prophylaxis, due to the low positive predictive value (PPV; 10%-15%) of the currently available predictive models. To stratify patients at high risk of developing CNS relapse, we retrospectively analyzed 182 patients with DLBCL initially treated with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP), or a R-CHOP-like regimen. Among them, 17 patients relapsed with CNS involvement, and the 2-year rate of CNS relapse was 7.9%. Upon carrying out multivariate analysis, ≥3 extranodal sites and elevated soluble interleukin-2 receptor (sIL-2R) levels at diagnosis were identified as independent risk factors for CNS relapse. The 2-year and 3.5-year rates of CNS relapse were 57.1% and 78.6%, respectively, in patients with both elevated sIL-2R and ≥3 extranodal sites. Furthermore, combined use of these risk factors of both elevated sIL-2R and ≥3 extranodal sites resulted in a high PPV (71.4%), negative predictive value (93.1%), and overall accuracy (92.3%) for undergoing CNS relapse. In conclusion, we propose a simple and valuable tool to predict patients with DLBCL at very high risk of CNS relapse.

HIV/AIDS Associated Lymphoma: Review

Lymphoma is one of the hematologic malignancies that occur at a higher rate in human immunodeficiency virus-infected individuals. It is one of the most frequent neoplastic causes of death in those individuals. Non-Hodgkin's lymphoma and Hodgkin's lymphomas are acquired immunodeficiency syndrome defining lymphoma and non-acquired immunodeficiency syndrome defining lymphoma, respectively. Non-Hodgkin's lymphoma is the most common type of lymphoma in human immunodeficiency virus-positive people. The lymphoma that develops in patients infected with the human immunodeficiency virus/acquired immunodeficiency syndrome is heterogeneous in terms of morphology, pathogenesis pathways, and cellular derivation. A narrative review was conducted on the basis of relevant literature on the current topic to summarize the current epidemiology, pathogenesis, laboratory diagnosis, and treatment of lymphoma in human immunodeficiency virus-infected patients. The finding showed that although the incidence of non-Hodgkin's lymphoma has decreased after the advent of highly active antiretroviral therapy, it has remained higher in human immunodeficiency virus-infected people than in the general population. On the other hand, the incidence of Hodgkin's lymphoma has increased after the introduction of highly active antiretroviral therapy. Therefore, it is recommended that people living with human immunodeficiency virus/ acquired immunodeficiency syndrome be screened for the development of lymphoma to increase their survival time and quality of life, and further research is required regarding the pathogenesis, treatment, and laboratory diagnosis of human immunodeficiency virus/ acquired immunodeficiency syndrome-associated lymphoma.

Vital Hepatic Lymphoma Residuum or Excessive Immune Response? Challenging Treatment Decisions in a Patient With Systemic Lupus Erythematosus and Liver-Dominant Diffuse Large B-Cell Lymphoma: Case Report

A 28-year-old female patient with active and difficult-to-treat systemic lupus erythematosus (SLE) was diagnosed with liver-dominant diffused large B-cell lymphoma. Repeated response ¹⁸F-FDG-PET studies showed persistently high, and, despite intensified immunochemotherapy, further increasing metabolic activity of one of the hepatic lymphoma residuals, whereas all other initial lymphoma manifestations had achieved complete metabolic remission. As biopsy of the ¹⁸F-FDG-PET-positive liver residual turned out to be inconclusive, complete resection was performed. Subsequent histopathological examination, however, revealed only necrotic tissue. Thus, no further lymphoma treatment was scheduled. The patient undergoes regular surveillance and is disease-free 13 months after resection. Similarly, treatment of SLE is no longer required due to lack of activity already after the first two cycles of lymphoma treatment. The case shows how closely SLE and diffused large B-cell lymphoma can be connected and stresses the importance of interdisciplinary treatment approaches. In the future, artificial intelligence may help to further classify ¹⁸F-FDG-PET-positive lymphoma residuals. This could lead to an increase of the positive predictive value of interim- and end-of-treatment ¹⁸F-FDG-PET. The patient’s point of view enables another instructive perspective on the course of treatment, which often remains hidden to treating physicians due to lack of time in clinical routine.

Timing of high dose methotrexate CNS prophylaxis in DLBCL: a multicenter international analysis of 1,384 patients

Prophylactic high-dose methotrexate (HD-MTX) is often used for diffuse large B-cell lymphoma (DLBCL) patients at high risk of central nervous system (CNS) relapse, despite limited evidence demonstrating efficacy or the optimal delivery method. We conducted a retrospective, international analysis of 1,384 patients receiving HD-MTX CNS prophylaxis either intercalated (i-HD-MTX) (n=749) or at the end (n=635) of R-CHOP/R-CHOP-like therapy (EOT). There were 78 CNS relapses (3-year rate 5.7%), with no difference between i-HD-MTX and EOT; 5.7% vs 5.8%, p=0.98, 3-year difference: 0.04% (-2.0% to 3.1%). Conclusions were unchanged on adjusting for baseline prognostic factors or on 6-month landmark analysis (n=1,253). In patients with high CNS international prognostic index (n=600), 3-year CNS relapse rate was 9.1% with no difference between i-HD-MTX and EOT. On multivariable analysis, increasing age and renal/adrenal involvement were the only independent risk factors for CNS relapse. Concurrent intrathecal prophylaxis was not associated with reduction in CNS relapse. R-CHOP delays of ≥7 days were significantly increased with i-HD-MTX versus EOT, with 308/1573 (19.6%) i-HD-MTX treatments resulting in delay to subsequent R-CHOP (median 8 days). Increased risk of delay occurred in older patients when delivery was later than day 10 in the R-CHOP cycle. In summary, we found no evidence that EOT delivery increases CNS relapse risk versus i-HD-MTX. Findings in high-risk subgroups were unchanged. Rates of CNS relapse in this HD-MTX-treated cohort were similar to comparable cohorts receiving infrequent CNS prophylaxis. If HD-MTX is still considered for certain high-risk patients, delivery could be deferred until R-CHOP completion.

Central nervous system (CNS) prophylaxis in antiCD20-CHOP treated DLBCL at intermediate to high risk for CNS relapse: A systematic review and meta-analysis

CNS prophylaxis is commonly used in Diffuse Large B-Cell Lymphoma (DLBCL) patients with risk features for CNS relapse. This systematic review and meta-analysis compares CNS relapse rates with and without CNS prophylaxis, for patients at intermediate to high CNS relapse risk. Studies reporting CNS relapse risk category and CNS outcomes with and without CNS prophylaxis for antiCD20-CHOP treated DLBCL patients were included. 10 studies with 3770 patients at intermediate to high CNS relapse risk were analyzed. No significant difference in the pooled Absolute Risk Difference (ARD 0.01, 95 % CI -0.01 to 0.02, P = 0.61) or Risk (RR 1.22, 95 % CI 0.81-1.83, P = 0.34) was noted in patients with and without CNS prophylaxis. There were also no differences within pre-specified subgroups of IV Methotrexate or IT chemotherapy. However, the quality of evidence supporting these observations was low. A meta-analysis of individual patient data will help evaluate the benefit of CNS prophylaxis strategies.

Detection of clonotypic DNA in the cerebrospinal fluid as a marker of central nervous system invasion in lymphoma

The NGS-MRD assay detected clonotypic DNA in 100% of CSF samples from patients who had lymphoma with parenchymal CNS involvement.

Clonotypic DNA in CSF was present in 36% of newly diagnosed aggressive lymphomas and was associated with a 29% risk of CNS recurrence.

The diagnosis of parenchymal central nervous system (CNS) invasion and prediction of risk for future CNS recurrence are major challenges in the management of aggressive lymphomas, and accurate biomarkers are needed to supplement clinical risk predictors. For this purpose, we studied the results of a next-generation sequencing (NGS)–based assay that detects tumor-derived DNA for clonotypic immunoglobulin gene rearrangements in the cerebrospinal fluid (CSF) of patients with lymphomas. Used as a diagnostic tool, the NGS-minimal residual disease (NGS-MRD) assay detected clonotypic DNA in 100% of CSF samples from 13 patients with known CNS involvement. They included 7 patients with parenchymal brain disease only, whose CSF tested negative by standard cytology and flow cytometry, and 6 historical DNA aliquots collected from patients at a median of 39 months before accession, which had failed to show clonal rearrangements using standard polymerase chain reaction. For risk prognostication, we prospectively collected CSF from 22 patients with newly diagnosed B-cell lymphomas at high clinical risk of CNS recurrence, of whom 8 (36%) had detectable clonotypic DNA in the CSF. Despite intrathecal prophylaxis, a positive assay of CSF was associated with a 29% cumulative risk of CNS recurrence within 12 months of diagnosis, in contrast with a 0% risk among patients with negative CSF (P = .045). These observations suggest that detection of clonotypic DNA can aid in the diagnosis of suspected parenchymal brain recurrence in aggressive lymphoma. Furthermore, the NGS-MRD assay may enhance clinical risk assessment for CNS recurrence among patients with newly diagnosed lymphomas and help select those who may benefit most from novel approaches to CNS-directed prophylaxis.

High-dose methotrexate is effective for prevention of isolated CNS relapse in diffuse large B cell lymphoma

The role of central nervous system (CNS) prophylaxis with high-dose methotrexate (HDMTX) in DLBCL is controversial. In this retrospective study, we evaluated the efficacy of prophylactic HDMTX on isolated CNS relapse, concomitant CNS and systemic relapse, systemic relapse, and survival outcomes in 226 patients with newly diagnosed DLBCL and high-risk CNS International Prognostic Index (CNS-IPI) score treated with RCHOP. The three-year risk of isolated CNS relapse was significantly lower in patients who received HDMTX, at 3.1% compared to 14.6% (P = 0.032) in those who did not. However, neither concomitant CNS-systemic relapse rates, systemic relapse rates, nor three-year PFS and OS were significantly different between treatment groups in multivariable analysis. Among propensity score-matched patients (N = 102), HDMTX was also associated with significantly lower isolated CNS relapse rates (HR 0.06, 95% CI 0.004–0.946, P = 0.046). HDMTX was well tolerated with manageable toxicities when given at a dose of 3 g/m² by day 3 of RCHOP chemotherapy. Using propensity score matching and multivariable regression to yield treatment groups with well-balanced covariates, we showed that prophylactic HDMTX improved isolated CNS relapse rates but did not decrease concomitant CNS-systemic relapse rates, systemic relapse rates, or improve survival outcomes.

Limited-stage diffuse large B-cell lymphoma: current management and challenges

Twenty-five to thirty per cent of diffuse large B-cell lymphoma (DLBCL) presents as limited stage (I-II). Prognosis is generally excellent with four to six cycles of R-CHOP alone (rituximab, cyclophosphamide, vincristine, doxorubicin, prednisolone) or combined-modality therapy with three or four cycles and involved-site radiotherapy (RT). There is growing interest in optimising algorithms to retain disease control whilst minimising long-term toxicity, with several recent studies focusing on the safety of abbreviating chemotherapy and omitting RT in low-risk patients and the utility of PET-based response-adapted approaches. As these studies are limited to younger patients without risk factors, application of similar approaches in elderly or higher-risk patients is hampered by a lack of evidence. Whilst there has been a move away from using RT in low-risk patients, it remains a useful adjunct in specific situations. Current evidence cannot exclude a clinically meaningful benefit from RT even in low-risk patients and, given the low expected toxicity from modern RT techniques, a risk-benefit assessment should be individualised and considered in a multidisciplinary fashion. The optimal approach for extranodal limited-stage DLBCL (~40% of cases) varies according to site of origin. Herein we discuss the latest clinical trial evidence and how this can be applied in routine practice.

Ineffectiveness of high-dose methotrexate for prevention of CNS relapse in diffuse large B-cell lymphoma

Central nervous system (CNS) relapse affects 5% of diffuse large B-cell lymphoma (DLBCL) patients and portends a poor prognosis. Prophylactic intravenous high-dose methotrexate (HD-MTX) is frequently employed to reduce this risk, but there is limited evidence supporting this practice. We conducted a multicenter retrospective study to determine the CNS relapse risk with HD-MTX in DLBCL patients aged 18-70 years treated in Alberta, Canada between 2012 and 2019. Provincial guidelines recommended HD-MTX for patients at high-risk of CNS relapse based upon CNS-IPI score, double-hit lymphoma, or testicular involvement. Among 906 patients with median follow-up 35.3 months (range 0.29-105.7), CNS relapse occurred in 1.9% with CNS-IPI 0-1, 4.9% with CNS-IPI 2-3, and 12.2% with CNS-IPI 4-6 (p < .001). HD-MTX was administered to 115/326 (35.3%) high-risk patients, of whom 96 (83.5%) had CNS-IPI score 4-6, 45 (39.1%) had double-hit lymphoma, and four (3.5%) had testicular lymphoma. The median number of HD-MTX doses was two (range 1-3). Central nervous system relapse risk was similar with versus without HD-MTX (11.2% vs. 12.2%, p = .82) and comparable to previous reports of high-risk patients who did not receive CNS prophylaxis (10-12%). In multivariate and propensity score analyses, HD-MTX demonstrated no association with CNS relapse, progression-free survival, or overall survival. This study did not demonstrate a benefit of prophylactic HD-MTX in this high-risk patient population. Further study is required to determine the optimal strategy to prevent CNS relapse in DLBCL.

Blame it on the pump

Although intrathecal pumps may lead to spinal symptoms that are likely related to the pump itself, the case presented herein underscores the importance of casting a broad differential diagnosis at the time of initial presentation.