A medical research council randomized trial in patients with primary cerebral non-Hodgkin lymphoma

Myeloablative vs nonmyeloablative consolidation for primary central nervous system lymphoma: results of Alliance 51101

ABSTRACT

Although it is evident that standard-dose whole-brain radiotherapy as consolidation is associated with significant neurotoxicity, the optimal consolidative strategy for primary central nervous system lymphoma (PCNSL) is not defined. We performed a randomized phase 2 clinical trial via the US Alliance cancer cooperative group to compare myeloablative consolidation supported by autologous stem cell transplantation with nonmyeloablative consolidation after induction therapy for PCNSL. To our knowledge, this is the first randomized trial to be initiated that eliminates whole-brain radiotherapy as a consolidative approach in newly diagnosed PCNSL. Patients aged 18 to 75 years were randomly assigned in a 1:1 manner to induction therapy (methotrexate, temozolomide, rituximab, and cytarabine) followed by consolidation with either thiotepa plus carmustine and autologous stem cell rescue vs induction followed by nonmyeloablative, infusional etoposide plus cytarabine. The primary end point was progression-free survival (PFS). A total of 113 patients were randomized, and 108 (54 in each arm) were evaluable. More patients in the nonmyeloablative arm experienced progressive disease or death during induction (28% vs 11%; P = .05). Thirty-six patients received autologous stem cell transplant, and 34 received nonmyeloablative consolidation. The estimated 2-year PFS was higher in the myeloablative vs nonmyeloablative arm (73% vs 51%; P = .02). However, a planned secondary analysis, landmarked at start of the consolidation, revealed that the estimated 2-year PFS in those who completed consolidation therapy was not significantly different between the arms (86% vs 71%; P = .21). Both consolidative strategies yielded encouraging efficacy and similar toxicity profiles. This trial was registered at www.clininicals.gov as #NCT01511562.

Primary central nervous system lymphomas: EHA-ESMO Clinical Practice Guideline for diagnosis, treatment and follow-up

This EHA-ESMO Clinical Practice Guideline provides key recommendations for managing primary DLBCL of the CNS.The guideline covers clinical, imaging and pathological diagnosis, staging and risk assessment, treatment and follow-up.Algorithms for first-line and salvage treatments are provided.The author group encompasses a multidisciplinary group of experts from different institutions and countries in Europe.Recommendations are based on available scientific data and the authors' collective expert opinion.

Comparison of differing dose levels of methotrexate for patients with primary central nervous system lymphoma

INTRODUCTION

It has long been established that high-dose methotrexate is an essential part of therapy for primary central nervous system lymphoma. When regimens utilizing high-dose methotrexate were first studied, a dose of 8 g/m2 was used. More recently, reduced dosing strategies have been studied and adopted in attempts to reduce rates of adverse events. Studies utilizing 3.5 g/m2 of methotrexate have shown promising outcomes and improved rates of adverse events but there have never been any randomized head-to-head studies of differing dose levels of high-dose methotrexate. The purpose of this study was to compare efficacy and safety of different dosing strategies of high-dose methotrexate (HD-MTX) for primary central nervous system lymphoma (PCNSL).

METHODS

This single center retrospective review was conducted between 07/01/2013 to 6/3/2020. The patient population was separated into two arms based upon dose of methotrexate. The high intensity (HiHD) arm was defined as patients who received doses > 3.5 g/m2, while the low intensity (LiHD) arm received ≤ 3.5 g/m2. The primary endpoint was overall response rate (ORR) and secondary endpoints include efficacy via 2-year overall survival (OS), progression to transplant, and utilization of consolidation or salvage therapy. Safety was assessed through monitoring of relevant laboratory studies.

RESULTS

A total of 92 patients were included in this analysis. Baseline demographics were similar between groups, with the LiHD group trending toward older age. There were 78 patients eligible for assessment for ORR; there was no significant difference between the two groups (42.0% LiHD vs. 44.4% HiHD; p = 1.0). Rates of OS, progression to transplant and progression to consolidation chemotherapy were not different between groups. There were statistically significantly higher rates of renal and/or hepatic dysfunction with the first dose in the HiHD group compared with the LiHD group (11.5% LiHD vs. 64.3% HiHD; p ≤ 0.01).

CONCLUSIONS

In this PCNSL patient cohort, there is no difference in terms of efficacy between HiHD LiHD methotrexate, but patients in the HiHD group had higher rates of renal and hepatic dysfunction. Limitations include small sample size and disparity between group sizes.

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.

Immunochemotherapy or chemotherapy alone in primary central nervous system lymphoma: a National Cancer Database analysis

Debate remains over the role of rituximab, a large molecule with reduced central nervous system (CNS) penetration, in therapy for primary CNS lymphoma (PCNSL). Since 2013, the National Cancer Database has distinguished between chemotherapy and immunotherapy for frontline treatment. In this setting, rituximab would be the only standard frontline immunotherapy. We examined factors associated with the receipt of immunotherapy using a multivariate regression model for relative risk, with a random intercept to account for the hospital-specific treatment selection process. Patients were matched using a 1:1 propensity score to limit possible confounders, and overall survival (OS) was compared in the matched cohort. We identified 4691 patients with PCNSL diagnosed between 2013 and 2018. The use of immunotherapy has increased from 45% in 2013 to 76% in 2018. Immunotherapy use was associated with sociodemographic variables and local (hospital level) preference rather than clinical factors. The main factors associated with reduced use of immunotherapy included male sex, Black race or Hispanic ethnicity (compared with White non-Hispanic), HIV+ status, treatment in a lower-volume hospital, and earlier year of diagnosis. We matched 2830 patients for the survival analysis. Receipt of immunotherapy was associated with a significantly better OS (hazard ratio [HR], 0.75; 95% confidence interval [CI], 0.67-0.83). There was heterogeneity according to age, because the advantage of immunotherapy was more pronounced for patients aged ≤75 years (HR, 0.71; 95% CI, 0.63-0.80) than for those older than 75 years (HR, 0.87; 95% CI, 0.70-1.08). Overall, our findings support the current trend toward rituximab use, although a nuanced approach should be adopted when treating older patients.

Leukemic infiltration of the optic nerve in chronic lymphocytic leukemia: A case report and review of literature

Ophthalmic and neurologic involvement are rare complications of CLL, with few cases reported in the literature. We report a case of CLL with leukemic infiltration of the optic nerve and review of literature focusing on management and outcomes. A patient with heavily pretreated CLL presented to our hospital with progressive eye pain and was found to have infiltrative optic neuritis. CSF analysis confirmed involvement with CLL. After systemic treatment with R-CHOP and high-dose methotrexate, along with intrathecal cytarabine and hydrocortisone, she experienced significant improvement and was discharged home. Given the rarity of ophthalmic involvement in CLL, we reviewed all 15 previously reported cases of CLL with optic neuropathy as the first manifestation of CNS involvement and discussed the range of treatment options used and their respective outcomes.

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.

Treatment Strategies and Prognostic Factors in Secondary Central Nervous System Lymphoma: A Multicenter Study of 124 Patients

Secondary central nervous system lymphoma (SCNSL) is a rare and difficult to treat type of Non-Hodgkin lymphoma characterized by systemic and central nervous system (CNS) disease manifestations. In this study, 124 patients with SCNSL intensively treated and with clinical long-term follow-up were included. Initial histopathology, as divided in low-grade, other aggressive, and diffuse large B-cell lymphoma (DLBCL), was of prognostic significance. Overall response to induction treatment was a prognostic factor with early responding DLBCL-SCNSL in comparison to those non-responding experiencing a significantly better progression-free survival (PFS) and overall survival (OS). However, the type of induction regime was not prognostic for survival. Following consolidating high-dose chemotherapy and autologous stem cell transplantation (HDT-ASCT), DLBCL-SCNSL patients had better median PFS and OS. The important role of HDT-ASCT was further highlighted by favorable responses and survival of patients not responding to induction therapy and by excellent results in patients with de novo DLBCL-SCNSL (65% long-term survival). SCNSL identified as a progression of disease within 6 months of initial systemic lymphoma presentation represented a previously not appreciated subgroup with particularly dismal outcome. This temporal stratification model of SCNSL diagnosis revealed CNS progression of disease within 6 months as a promising candidate prognosticator for future studies.

Reciprocal expression of the immune response genes CXCR3 and IFI44L as module hubs are associated with patient survivals in primary central nervous system lymphoma

PURPOSE

Here, we investigated expression modules reflecting the reciprocal expression of the cancer microenvironment and immune response-related genes associated with poor prognosis in primary central nervous system lymphoma (PCNSL).

METHODS

Weighted gene coexpression network analysis revealed representative modules, including neurogenesis, immune response, anti-virus, microenvironment, gene expression and translation, extracellular matrix, morphogenesis, and cell adhesion in the transcriptome data of 31 PCNSL samples. RESULTS : Gene expression networks were also reflected by protein-protein interaction networks. In particular, some of the hub genes were highly expressed in patients with PCNSL with prognoses as follows: AQP4, SLC1A3, GFAP, CXCL9, CXCL10, GBP2, IFI6, OAS2, IFIT3, DCN, LRP1, and LUM with good prognosis; and STAT1, IFITM3, GZMB, ISG15, LY6E, TGFB1, PLAUR, MMP4, FTH1, PLAU, CSF3R, FGR, POSTN, CCR7, TAS1R3, small ribosomal subunit genes, and collagen type 1/3/4/6 genes with poor prognosis. Furthermore, prognosis prediction formulae were constructed using the Cox proportional-hazards regression model, which demonstrated that the IP-10 receptor gene CXCR3 and type I interferon-induced protein gene IFI44L could predict patient survival in PCNSL.

CONCLUSION

These results indicate that the differential expression and balance of immune response and microenvironment genes may be required for PCNSL tumor growth or prognosis prediction, which would help understanding the mechanism of tumorigenesis and potential therapeutic targets in PCNSL.

Long-term outcomes with reduced-dose whole-brain radiotherapy and a stereotactic radiosurgery boost for primary central nervous system lymphoma

Background

Primary central nervous system lymphoma (PCNSL) is an aggressive diffuse large B-cell lymphoma. Treatment approaches are historically associated with neurotoxicity, particularly with high-dose whole-brain radiotherapy (WBRT). We hypothesized that reduced dose-WBRT (rd-WBRT) followed by a stereotactic radiosurgery (SRS) boost could provide durable disease control without significant adverse effects.

Methods

We retrospectively reviewed PCNSL patients treated with rd-WBRT plus an SRS boost at Duke University between 2008 and 2021. Progression-free survival and overall survival (OS) were estimated using competing risk and Kaplan-Meier methods.

Results

We identified 23 patients with pathologically confirmed PCNSL. Median age at diagnosis was 69 years (Q1Q3: 52-74) and median Karnofsky Performance Scale (KPS) was 80 (Q1Q3: 70-80). Median follow-up was 21 months. Median doses for rd-WBRT and SRS were 23.4 Gy (Q1Q3: 23.4-23.4) and 12 Gy (Q1Q3: 12-12.5), respectively. The cumulative incidence of intracranial progression at 2 years was 23% (95% CI: 8-42). Six patients (26%) developed distant radiographic progression while 2 patients (9%) developed both distant and local progression. Ten patients (44%) were alive without progression at last follow-up. By Kaplan-Meier estimate, the 2-year OS was 69% (95% CI: 46-84). There were no reported grade 3 + radiation-induced toxicities.

Conclusions

The combination of rd-WBRT with an SRS boost appears well-tolerated with durable intracranial control. This approach may represent a treatment option for select patients, such as those with progressive or refractory disease. Further prospective studies are needed to validate these findings and determine whether this approach could be incorporated into consolidation strategies.

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.

Intravascular Large B Cell Lymphoma with CNS Involvement Successfully Treated with High-Dose Methotrexate and High-Dose Ara-C Based CNS-Directed Chemoimmunotherapy Alternating with Anthracycline Based Chemoimmunotherapy

Intravascular large B cell lymphoma (IVL) is a rare subtype of diffuse large B cell lymphoma confined to small blood vessels with a predilection for CNS involvement. The prognosis of IVL with CNS involvement (CNS-IVL) is extremely poor. The optimal treatment for CNS-IVL is not well defined. Thus, we report three patients with CNS-IVL successfully treated with a CNS-centric approach consisting of high-dose methotrexate (HDMTX) and high-dose Ara-C (HiDAC) based CNS-directed chemoimmunotherapy (CIT) alternating with anthracycline-based CIT. Our rationale for intensifying the CNS-directed therapy is the presence of intracerebral bleeding in two of our patients which would result in extravasation of lymphoma cells into the cerebral parenchyma with the development of CNS lymphoma. All three patients have achieved excellent therapeutic outcomes. Two patients with intracerebral bleeding have been in complete remission (CR) for about 11 years and 4 years. One patient was successfully induced into CR about 10 months ago and currently is in CR. This unique therapeutic approach should be further explored for CNS-IVL.

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.

Ibrutinib in Refractory or Relapsing Primary Central Nervous System Lymphoma: A Systematic Review

Primary Central Nervous System Lymphoma (PCNSL) is a rare variant of Non-Hodgkin Lymphoma (NHL) representing 1–2% of all NHL cases. PCNSL is defined as a lymphoma that occurs in the brain, spinal cord, leptomeninges, or eyes. Efforts to treat PCNSL by traditional chemotherapy and radiotherapy have generally been unsuccessful as a significant proportion of patients have frequent relapses or are refractory to treatment. The prognosis of patients with Refractory or Relapsed (R/R) PCNSL is abysmal. The optimal treatment for R/R PCNSL is poorly defined as there are only a limited number of studies in this setting. Several studies have recently shown that ibrutinib, a Bruton tyrosine kinase (BTK) inhibitor, has promising results in the treatment of R/R PCNSL. However, these are preliminary studies with a limited sample size. In this systematic review, we explored and critically appraised the evidence about the efficacy of the novel agent ibrutinib in treating R/R PCNSL.

Hypo-trimethylation of Histone H3 Lysine 4 and Hyper-tri/dimethylation of Histone H3 Lysine 27 as Epigenetic Markers of Poor Prognosis in Patients with Primary Central Nervous System Lymphoma

Purpose

This study aimed to investigate the methylation status of major histone modification sites in primary central nervous system lymphoma (PCNSL) samples and examine their prognostic roles in patients with PCNSL.

Materials and Method

Between 2007 and 2020, 87 patients were histopathologically diagnosed with PCNSL. We performed immunohistochemical staining of the formalin-fixed paraffin-embedded samples of PCNSL for major histone modification sites, such as H3K4, H3K9, H3K27, H3K14, and H3K36. After detection of meaningful methylation sites, we examined histone modification enzymes that induce methylation or demethylation at each site using immunohistochemical staining. The meaningful immunoreactivity was validated by western blotting using fresh tissue of PCNSL.

Results

More frequent recurrences were found in hypomethylation of H3K4me3 (p=0.004) and hypermethylation of H3K27me2 (p<0.001) and H3K27me3 (p=0.002). These factors were also statistically related to short PFS and OS in the univariate and multivariate analyses. Next, histone modification enzymes inducing the demethylation of H3K4 (lysine-specific demethylase (LSD)-1/2 and Jumonji AT-rich interactive domain 1A (JARID1A-D)) and methylation of H3K27 (enhancer of zeste homolog (EZH)-1/2) were immunohistochemically stained. Among them, the immunoreactivity of JARID1A inversely associated with the methylation status of H3K4me3 (R2=-1.431), and immunoreactivity of EZH2 was directly associated with the methylation status of H3K27me2 (R2=0.667) and H3K27me3 (R2=0.604). These results were validated by western blotting in fresh PCNSL samples.

Conclusion

Our study suggests that hypomethylation of H3K4me3 and hypermethylation of H3K27me2 and H3K27me3 could be associated with poor outcomes in patients with PCNSL and that these relationships are modified by JARID1A and EZH2.

Clinical Outcomes of RTOG 9310 Protocol for Primary Central Nervous System Lymphoma: Single-Center Experience with 87 Patients

The Radiation Therapy Oncology Group (RTOG) 9310 protocol clinical trial established high-dose methotrexate (HDMTX) as the standard for primary central nervous system lymphoma (PCNSL). We aimed to investigate the RTOG 9310 protocol’s PCNSL outcomes by examining progression-free survival (PFS) and overall survival (OS) rates and determining the influential factors. Between 2007 and 2020, 87 patients were histopathologically diagnosed with PCNSL and treated with the RTOG 9310 protocol. All received HDMTX 2.5 g/m² and vincristine 1.4 mg/m²/day for 1 day during weeks 1, 3, 5, 7, and 9, and procarbazine 100 mg/m²/day for 1 day during weeks 1, 5, and 9. Dexamethasone was administered on a standard tapering schedule from the first week to the sixth week. Whole brain radiotherapy (WBRT), consisting of 45 Gy for patients with less than a complete response to the chemotherapy or 36 Gy for complete responders, was started 1 week after the last dose of chemotherapy was administered. Within three weeks of the completion of WBRT, patients received two courses of cytarabine, which were separated by 3–4 weeks. Clinical, radiological, and histopathological characteristics were retrospectively reviewed. All patients completed five HDMTX cycles and a mean follow-up of 60.2 (range, 6–150) months. Twenty-eight (32.2%) patients experienced recurrence during follow-up. The mean time to recurrence was 21.8 months, while the mean PFS was 104.3 (95% confidence interval (CI), 90.6–118.0) months. Eleven (12.6%) patients died; the mean OS was 132.1 (95% CI, 122.2–141.9) months. The 3- and 5-year survival rates were 92.0% and 87.4%, respectively. One patient experienced acute renal failure, while the remainder tolerated any cytotoxic side effects. On multivariate analysis, the Eastern Cooperative Oncology Group performance score ≤ 2; the International Extranodal Lymphoma Study Group low-risk status; XBP-1, p53, and c-Myc negativity; homogenous enhancement; gross total resection, independently correlated with long PFS and OS. The RTOG 9310 protocol is effective for PCNSL and features good outcomes.

Analysis of Cellular Heterogeneity in Immune Microenvironment of Primary Central Nervous System Lymphoma by Single-Cell Sequencing

Background

Primary central nervous system lymphoma (PCNSL) is characterized by a lack of specificity and poor prognosis. Further understanding of the tumor heterogeneity and molecular phenotype of PCNSL is of great significance for improving the diagnosis and treatment of this disease.

Methods

To explore the distinct phenotypic states of PCNSL, transcriptome-wide single-cell RNA sequencing was performed on 34,851 PCNSL cells from patients. The cell types, heterogeneity, and gene subset enrichment of PCNSL were identified. A comparison of the PCNSL cells with 21,250 normal human fetal brain (nHFB) cells was further analyzed to reveal the differences between PCNSL and normal sample.

Results

Six cell populations were mainly identified in the PCNSL tissue, including four types of immune cells—B cell, T cell, macrophage and dendritic cell—and two types of stromal cells: oligodendrocyte and meningeal cell. There are significant cellular interactions between B cells and several other cells. Three subpopulations of B cells indicating diffident functions were identified, as well as a small number of plasma cells. Different subtypes of T cells and dendritic cells also showed significant heterogeneity. It should be noted that, compared with normal, the gene expression and immune function of macrophages in PCNSL were significantly downregulated, which may be another important feature of PCNSL in addition to B cell lesions and may be a potential target for PCNSL therapy.

Clinical Features and Prognostic Factors for Primary Anaplastic Large Cell Lymphoma of the Central Nervous System: A Systematic Review

Simple Summary

Primary anaplastic large cell lymphoma (ALCL) of the central nervous system (CNS) is a subtype of primary central nervous system lymphoma (PCNSL). ALCL is divided into anaplastic lymphoma kinase (ALK)-positive ALCL and ALK-negative ALCL, according to ALK expression. ALK-positive cancers tend to develop at a younger age and tend to have a better prognosis. Almost all past articles on primary ALCL of the CNS have been case reports and there have been no randomized trials or cohort studies on this subject. We thus performed a systematic review of primary ALCL of the CNS. According to the author’s survey, 36 case reports have been published in English-language journals. In this paper, we have summarized the clinical features and prognostic factors for primary ALCL of the CNS based on previous studies.

Abstract

Primary anaplastic large cell lymphoma (ALCL) of the central nervous system (CNS) is a subtype of primary CNS lymphoma (PCNSL). There are very few comprehensive reports on this extremely rare tumor. Therefore, it is necessary to investigate the clinical features and prognostic factors for primary ALCL of the CNS. We performed a systematic review of the published literature. Past cases were comprehensively searched using PubMed, Cochrane Library, and Web of Science. Clinical information, such as age, sex, anaplastic lymphoma kinase (ALK) status, lesion sites, treatment methods, and survivorship were extracted. Thirty-nine cases with information on ALK status and treatment course were identified. The average observation period was 13 months, and the overall 2-year survival rate was 58%. Univariate analyses showed a statistically significantly better prognosis among patients < 40 years of age (p = 0.039, HR 0.32 (0.11–0.95)) and in relation to ALK positivity (p = 0.010, HR 0.24 (0.08–0.71) and methotrexate treatment (p = 0.003, HR 0.17 (0.05–0.56)). Because of the sparsity of cases, it is necessary to accumulate cases in order to perform more detailed analyses.

Treatment Regimens for Immunocompetent Elderly Patients with Primary Central Nervous System Lymphoma: A Scoping Review

Simple Summary

Most patients diagnosed with primary central nervous system lymphoma (PCNSL) are 60 years or older and tend to have a poor prognosis. Evidence to guide and optimize treatment choices for these vulnerable patients is limited. We performed a scoping review to identify and describe all relevant clinical studies investigating chemotherapies and combinations of chemotherapies (including high-dose chemotherapy followed by autologous stem cell transplantation (HCT-ASCT)) in elderly PCNSL patients. In total, we identified six randomized controlled trials, 26 prospective and 24 retrospective studies (with/without control group). While most studies investigated protocols based on ‘conventional’ chemotherapy treatment, data evaluating HCT-ASCT in the elderly were scarce, and the generalizability of the only RCT published is questionable. Considering the poor prognosis of these patients and their need for more effective treatment options, a thoroughly planned randomized controlled trial comparing HCT-ASCT with ‘conventional’ chemoimmunotherapy is urgently needed to evaluate the efficacy of HCT-ASCT.

Abstract

Background: Most patients diagnosed with primary central nervous system lymphoma (PCNSL) are older than 60 years. Despite promising treatment options for younger patients, prognosis for the elderly remains poor and efficacy of available treatment options is limited. Materials and Methods: We conducted a scoping review to identify and summarize the current study pool available evaluating different types and combinations of (immuno) chemotherapy with a special focus on HCT-ASCT in elderly PCNSL. Relevant studies were identified through systematic searches in the bibliographic databases Medline, Web of Science, Cochrane Library and ScienceDirect (last search conducted in September 2020). For ongoing studies, we searched ClinicalTrials.gov, the German study register and the WHO registry. Results: In total, we identified six randomized controlled trials (RCT) with 1.346 patients, 26 prospective (with 1.366 patients) and 24 retrospective studies (with 2.629 patients). Of these, only six studies (one completed and one ongoing RCT (with 447 patients), one completed and one ongoing prospective single arm study (with 65 patients), and two retrospective single arm studies (with 122 patients)) evaluated HCT-ASCT. Patient relevant outcomes such as progression-free and overall survival and (neuro-)toxicity were adequately considered across almost all studies. The current study pool is, however, not conclusive in terms of the most effective treatment options for elderly. Main limitations were (very) small sample sizes and heterogeneous patient populations in terms of age ranges (particularly in RCTs) limiting the applicability of the results to the target population (elderly). Conclusions: Although it has been shown that HCT-ASCT is probably a feasible and effective treatment option, this approach has never been investigated within a RCT including a wide range of elderly patients. A RCT comparing conventional (immuno) chemotherapy with HCT-ASCT is crucial to evaluate benefit and harms in an un-biased manner to eventually provide older PCNSL patients with the most effective treatment.

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.

Cardiovascular Outcomes in the Patients With Primary Central Nervous System Lymphoma: A Multi-Registry Based Cohort Study of 4,038 Cases

Primary central nervous system lymphoma (PCNSL) is a rare but highly aggressive non-Hodgkin lymphoma. Treatment-related cardiovascular lesion has become one of the most common complications in patients with tumor. However, very little is known about the cardiovascular death (CVD) of the patients with PCNSL. This study aims at identifying the cardiovascular outcomes of PCNSL patients and making comparison on CVD with extra central nervous system lymphoma (ECNSL). Clinical information of PCNSL and ECNSL was retrieved from the Surveillance, Epidemiology and End Results database. The risk factors of CVD in PCNSL patients and the comparison on the CVD hazard between PCNSL and ECNSL were assessed with the competing risks regression. A 1:2 propensity score matching was used to reduce the imbalanced baseline characteristics between PCNSL and ECNSL. Four thousand thirty-eight PCNSL subjects and 246,760 ECNSL subjects were enrolled in this retrospective study. CVD was the leading cause (41.2%) of non-cancer death in PCNSL patients and mostly occurred within the first year of diagnosis. Age over 60s and diagnosis in 2000–2008 were significantly associated with the elevated risk of CVD in PCNSL patients, while chemotherapy and radiotherapy play no role on the cardiovascular outcomes. Compared with ECNSL patients, the risk of CVD in PCNSL patients were 40% approximately lower. The risk of CVD in the patients with PCNSL still remains unclear currently. Clinicians ought to pay more attention on the risk of CVD in PCNSL patients, especially the elder patients within the first year of diagnosis.

Improving the antitumor activity of R-CHOP with NGR-hTNF in primary CNS lymphoma: final results of a phase 2 trial

Rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) is the standard treatment of diffuse large B-cell lymphoma (DLBCL). Primary DLBCL of the central nervous system (CNS) (primary central nervous system lymphoma [PCNSL]) is an exception because of the low CNS bioavailability of related drugs. NGR-human tumor necrosis factor (NGR-hTNF) targets CD13+ vessels, enhances vascular permeability and CNS access of anticancer drugs, and provides the rationale for the treatment of PCNSL with R-CHOP. Herein, we report activity and safety of R-CHOP preceded by NGR-hTNF in patients with PCNSL relapsed/refractory to high-dose methotrexate-based chemotherapy enrolled in a phase 2 trial. Overall response rate (ORR) was the primary endpoint. A sample size of 28 patients was considered necessary to demonstrate improvement from 30% to 50% ORR. NGR-hTNF/R-CHOP would be declared active if ≥12 responses were recorded. Treatment was well tolerated; there were no cases of unexpected toxicities, dose reductions or interruptions. NGR-hTNF/R-CHOP was active, with confirmed tumor response in 21 patients (75%; 95% confidence interval, 59%-91%), which was complete in 11. Seventeen of the 21 patients with response to treatment received consolidation (ASCT, WBRT, and/or lenalidomide maintenance). At a median follow-up of 21 (range, 14-31) months, 5 patients remained relapse-free and 6 were alive. The activity of NGR-hTNF/R-CHOP is in line with the expression of CD13 in both pericytes and endothelial cells of tumor vessels. High plasma levels of chromogranin A, an NGR-hTNF inhibitor, were associated with proton pump inhibitor use and a lower remission rate, suggesting that these drugs should be avoided during TNF-based therapy. Further research on this innovative approach to CNS lymphomas is warranted. The trial was registered as EudraCT: 2014-001532-11.

Current and emerging therapies for primary central nervous system lymphoma

Primary central nervous system (CNS) lymphoma (PCNSL) is a rare type of extranodal lymphoma exclusively involving the CNS at the onset, with diffuse large B-cell lymphoma (DLBCL) as the most common histological subtype. As PCNSL is a malignancy arising in an immune-privileged site, suboptimal delivery of systemic agents into tumor tissues results in poorer outcomes in PCNSL than in non-CNS DLBCLs. Commonly used regimens for PCNSL include high-dose methotrexate-based chemotherapy with rituximab for induction therapy and intensive chemotherapy followed by autologous hematopoietic stem cell transplantation or whole-brain radiotherapy for consolidation therapy. Targeted agents against the B-cell receptor signaling pathway, microenvironment immunomodulation and blood-brain barrier (BBB) permeabilization appear to be promising in treating refractory/relapsed patients. Chimeric antigen receptor-T cells (CAR-T cells) have been shown to penetrate the BBB as a potential tool to manipulate this disease entity while controlling CAR-T cell-related encephalopathy syndrome. Future approaches may stratify patients according to age, performance status, molecular biomarkers and cellular bioinformation. This review summarizes the current therapies and emerging agents in clinical development for PCNSL treatment.

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.

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.

Primary cerebral lymphoma' characteristics, incidence, survival, and causes of death in the United States

PURPOSE

This study aimed to provide an updated overview of primary central lymphoma (PCL) using a large cohort of 33 years. That being said, we attempted to examine the patient demographics, management plans and their outcome, causes of death and the time trends in overall incidence and mortality rates of these patients.

METHODS

We conducted a retrospective cohort study using the Surveillance, Epidemiology, and End Results (SEER) database between 1983 and 2016. We calculated the frequencies and the average annual age-adjusted rate (AAR) of PCL patients. Uni- and multivariable accelerated failure time regression were used to identify possible prognostic factors affecting the patients' survival. Furthermore, detailed causes of death were extracted and joint point regression analysis was done to examine incidence and mortality trends.

RESULTS

We identified 2925 PCL cases. The AAR was 0.148 per 100,000. An increase in age was significantly associated with shorter survival (HR: 1.01, 95%CI = 1.01-1.01, P < .001), while a recent year of diagnosis after 1993-2002 and 2002 was associated with improved survival (HR: 0.76, CI = 0.65-0.89, P = .001), and (HR: 0.48, CI = 0.41-0.56, P < .001), respectively. Overall, the trend of mortality rates in PCL patients has declined over the past years (-1.38% per year).

CONCLUSION

Our results support the previous evidence by showing an increase in patients' survival over time. While most PCL-related deaths occur within the first year, subsequent slow progression was observed after the first few years of survival. More attention should be given to the other possible non-PCL causes of death, especially beyond ten years of survival.

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.

Cardiovascular adverse events in patients with non-Hodgkin lymphoma treated with first-line cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) or CHOP with rituximab (R-CHOP): a systematic review and meta-analysis

BACKGROUND

Patients treated for non-Hodgkin lymphoma are at risk of cardiovascular adverse events, with the risk of heart failure being particularly high. A regimen of cyclophosphamide, doxorubicin, vincristine, and prednisone, with (R-CHOP) or without (CHOP) rituximab is the standard first-line treatment for aggressive non-Hodgkin lymphoma, and doxorubicin and cyclophosphamide are both associated with left ventricular dysfunction. The aim of this systematic review and meta-analysis was to evaluate the cardiovascular toxicity of this regimen.

METHODS

We systematically searched PubMed, EMBASE, and the Cochrane Library from database inception to June 3, 2019, for clinical trials and observational studies in adult patients with non-Hodgkin lymphoma (diffuse large B-cell lymphoma, follicular lymphoma, mantle cell lymphoma, peripheral T-cell lymphoma, and non-Hodgkin lymphoma not otherwise specified) that received first-line treatment with R-CHOP or CHOP. Studies reporting on cardiovascular adverse events and treatment-related cardiovascular mortality were included. Abstracts and articles not written in English were excluded. The main outcomes were the proportion of patients with grade 3-4 cardiovascular adverse events and heart failure. Meta-analyses of one-sample proportions were done in all patients receiving CHOP or R-CHOP. Subgroup analyses on summary estimates were done to determine the effect of number of CHOP or R-CHOP cycles, cycle interval, age, and sex.

FINDINGS

Of 2314 identified entries, 137 studies (21 211 patients) published between April, 1984, and June, 2019 were eligible (9541 patients treated with CHOP, 11 293 patients treated with R-CHOP, 377 both regimens used in the study; median follow-up 39·0 months [IQR 25·5-52·8]). From the included studies, 85 subgroups were treated with CHOP, 76 with R-CHOP, and in four studies both CHOP and R-CHOP were used without a subdivision in separate groups. The pooled proportion for grade 3-4 cardiovascular adverse events, based on 77 studies (n=14 351 patients), was 2·35% (95% CI 1·81-2·93; heterogeneity test Q=326·21; τ²=0·0042; I²=71·40%; p<0·0001). For heart failure, the pooled proportion, based on 38 studies (n=5936 patients), was 4·62% (2·25-7·65; heterogeneity test Q=527·33; τ²=0·0384; I²=95·05%; p<0·0001), with a significant increase in reported heart failure from 1·64% (95% CI 0·82-2·65) to 11·72% (3·00-24·53) when cardiac function was evaluated post-chemotherapy (p=0·017). 53 (39%) of 137 studies were rated as having high risk of bias for incomplete outcome data and 54 (39%) for selective reporting.

INTERPRETATION

The considerable increase of reported heart failures with cardiac monitoring, indicates that this complication often remains undiagnosed in patients with non-Hodgkin lymphoma who received first-line R-CHOP or CHOP. Our findings are of importance to raise awareness of this complication among clinicians treating patients with non-Hodgkin lymphoma and stresses the need for cardiac monitoring during and after chemotherapy. Prompt initiation of treatment for heart failure in the presymptomatic phase can mitigate the progression to more advanced heart failure stages.

FUNDING

None.

Continuous intrathecal injection therapy of methotrexate is a therapeutic option in primary CNS lymphoma

Primary central nervous system lymphoma (PCNSL) is a rare subtype of non-Hodgkin's lymphoma, and its prognosis is still very poor despite the conventional therapy of high-dose methotrexate (HD-MTX) followed by whole-brain radiation therapy (WBRT). The purpose of the present study was to evaluate the survival benefit of continuous intrathecal injection therapy of methotrexate (CIT-MTX) combined with the conventional therapy. A total of 26 PCNSL patients treated with CIT-MTX were analyzed. Ten mg of methotrexate were continuously injected into the lateral ventricle via a subcutaneous port over 5 days biweekly for 5 cycles. CIT-MTX was performed with WBRT in addition to HD-MTX in 15 cases, and 11 cases with high risk for HD-MTX were treated with CIT-MTX and WBRT. The response rate of all patients was 92.3%, and median progression-free survival and median overall survival (mOS) were 59.4 months and 93.8 months, respectively. Median OS of patients treated with CIT-MTX in addition to HD-MTX and WBRT was longer than the previously reported mOS with HD-MTX and WBRT (95 vs 33 months). In cases that could not tolerate HD-MTX, mOS of patients treated with CIT-MTX and WBRT was longer than the previously reported mOS with WBRT alone (36.7 vs 18 months). There was no difference in OS between patients with cerebrospinal fluid dissemination and patients without (p = 0.83). Better prognosis in patients treated with CIT-MTX may be derived from stable concentration of methotrexate in the cerebrospinal fluid. CIT-MTX was an effective additional therapeutic option for PCNSL.

R-CHOP preceded by blood-brain barrier permeabilization with engineered tumor necrosis factor-α in primary CNS lymphoma

Patients with primary central nervous system lymphoma (PCNSL) are treated with high-dose methotrexate-based chemotherapy, which requires hospitalization and extensive expertise to manage related toxicity. The use of R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone) could overcome these difficulties, but blood-brain barrier (BBB) penetration of related drugs is poor. Tumor necrosis factor-α coupled with NGR (NGR-hTNF), a peptide targeting CD13⁺ vessels, induces endothelial permeabilization and improves tumor access of cytostatics. We tested the hypothesis that NGR-hTNF can break the BBB, thereby improving penetration and activity of R-CHOP in patients with relapsed/refractory PCNSL (NCT03536039). Patients received six R-CHOP21 courses, alone at the first course and preceded by NGR-hTNF (0.8 μg/m²) afterward. This trial included 2 phases: an "explorative phase" addressing the effect of NGR-hTNF on drug pharmacokinetic parameters and on vessel permeability, assessed by dynamic contrast-enhanced magnetic resonance imaging and ^99mTc-diethylene-triamine-pentacetic acid-single-photon emission computed tomography, and the expression of CD13 on tumor tissue; and an "expansion phase" with overall response rate as the primary end point, in which the 2-stage Simon Minimax design was used. At the first stage, if ≥4 responses were observed among 12 patients, the study accrual would have continued (sample size, 28). Herein, we report results of the explorative phase and the first-stage analysis (n = 12). CD13 was expressed in tumor vessels of all cases. NGR-hTNF selectively increased vascular permeability in tumoral/peritumoral areas, without interfering with drug plasma/cerebrospinal fluid concentrations. The NGR-hTNF/R-CHOP combination was well tolerated: there were only 2 serious adverse events, and grade 4 toxicity was almost exclusively hematological, which were resolved without dose reductions or interruptions. NGR-hTNF/R-CHOP was active, with 9 confirmed responses (75%; 95% confidence interval, 51-99), 8 of which were complete. In conclusion, NGR-hTNF/R-CHOP was safe in these heavily pretreated patients. NGR-hTNF enhanced vascular permeability specifically in tumoral/peritumoral areas, which resulted in fast and sustained responses.

miR-370 Sensitizes TMZ Response Dependent of MGMT Status in Primary Central Nervous System Lymphoma

Primary central nervous system lymphoma (PCNSL) is an aggressive and rare subtype of non-Hodgkin lymphoma, arising exclusively in the CNS with a poor prognosis. Previous evidence has proved that MGMT was a promising target involving in TMZ resistance of PCNSL. Our study described a new miR-370-mediated mechanism of MGMT regulation in PCNSL. We first showed that miR-370 was downregulated in PCNSL tissues, while MGMT was inversely overexpressed. It was also observed that miR-370 suppressed the expression of MGMT. Additionally, upregulation of miR-370 significantly increased TMZ sensitivity dependent of MGMT, thus suppressed Raji cell proliferation and induced apoptosis in vitro. In conclusion, these results suggest that miR-370 is a potential target in PCNSL treatment.

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.

Treatment of Primary Central Nervous System Lymphoma: From Chemotherapy to Small Molecules

Primary central nervous system lymphoma (PCNSL) is a rare form of extranodal non-Hodgkin lymphoma that is typically confined to the brain, eyes, and cerebrospinal fluid (CSF) without evidence of systemic spread. PCNSL is an uncommon tumor, and only four randomized trials and one phase III trial have been completed so far, all in the first-line setting. The prognosis of patients with PCNSL has improved during the past few decades with the introduction of high-dose methotrexate (HD-MTX), which now serves as the backbone of all first-line treatment regimens. Despite recent progress, results after treatment are durable in half of patients, and therapy can be associated with late neurotoxicity. Novel insights into the pathophysiology of PCNSL have identified the B-cell receptor (BCR) pathway as a key mechanism in the pathogenesis of PCNSL. The use of novel agents targeting components of the BCR pathway, namely the Bruton tyrosine kinase (BTK) inhibitor ibrutinib, and immunomodulatory drugs (IMIDs) like lenalidomide and pomalidomide, has so far been limited to patients who have recurrent/refractory PCNSL with promising high response rates. Within the past 5 years, there has been a peak in clinical trials investigating small molecules and novel reagents in the recurrent/refractory setting, including immune checkpoint inhibitors, IMIDs, and BTK and PI3K/AKT/mTOR inhibitors.

Challenges and prospects in the diagnosis and treatment of primary central nervous system lymphoma

Introduction: Primary central nervous system lymphoma (PCNSL) retains peculiar biological and clinical characteristics and a worse prognosis with respect to other comparable lymphomas. The need for high doses of chemotherapy to achieve valid drug concentrations in cerebral tissues and/or radiotherapy results in severe treatment-related toxicities, mainly neurologic, which are frequently as disabling as the disease itself.Areas covered: Several emerging combined therapies are addressed that focus on treating PCNSL. The prognosis has improved in the last years but several questions remain unanswered and the research of more effective therapies goes on. Information and data were obtained from direct authors' experience and a PubMed search of recent peer-reviewed original articles, review articles, and clinical guidelines.Expert commentary: The substantial progress observed in PCNSL has to be ascribed to a carefully combination of standard chemotherapeutic drugs. High-dose methotrexate-based polychemotherapy followed by mainteinance therapy offers one of the best chances to control the disease. Major issues that deserve many efforts by researchers are the definition of optimal consolidation treatment and a shared management of specific conditions such as elderly population and intra-ocular localization.

Novel biomarker, phosphorylated T-LAK cell-originated protein kinase (p-TOPK) can predict outcome in primary central nervous system lymphoma

This study aimed to assess whether T-lymphokine-activated killer cell-originated protein kinase (TOPK) can be a potent novel biomarker to predict the outcome in patients with primary central nervous system lymphoma (PCNSL). This study enrolled 20 patients who were histologically diagnosed as having diffuse large B-cell type PCNSL between 2005 and 2015. Using surgical specimens, the expression of TOPK and phosphorylated TOPK (p-TOPK) was analyzed on immunohistochemistry. Clinical features such as age, sex, Karnofsky performance status (KPS), ocular involvement, deep brain structure involvement, the number of lesions, chemotherapy and radiation therapy were also collected. Impacts of TOPK/p-TOPK expression on their progression-free survival (PFS) and overall survival (OS) were examined with multivariate analysis. Median PFS/OS were 24.2 and 39.0 months, respectively. On immunostaining, the mean percentage of TOPK-positive cells was 35.5 ± 20.8%, and the mean number of p-TOPK-positive cells was 13.7 ± 15.7 cells/mm² . The higher expression of p-TOPK was significantly related to multiple lesions (P = 0.003). Multivariate analysis demonstrated that only the higher expression of p-TOPK was an independent predictor to shorten both PFS (P = 0.029; hazard ratio (HR), 5.5; 95% confidential interval (CI), 1.2-25.3) and OS (P = 0.014; HR, 7.7; 95% CI, 1.5-41.3). These findings strongly suggest that p-TOPK may be a potent biomarker to determine the outcome of patients with PCNSL and to develop novel drugs to treat PCNSL.

The possible role of maintenance treatment for primary central nervous system lymphoma

Primary central nervous system lymphoma (PCNSL) is a rare and aggressive brain tumor. The prognosis is poor, with high rates of relapse and disease progression after treatment. In addition, PCNSL affects a largely older population, so that a significant proportion of patients are ineligible for intensive therapies and high-dose chemotherapy. The elderly patients are also susceptible to the accelerated and detrimental cognitive side effects of whole-brain irradiation which is an alternative consolidation to high-dose chemotherapy. Maintenance therapy has been shown to be a promising strategy to prolong remission time in other hematopoietic malignancies. Herein, we discuss the place of maintenance treatment in PCNSL in view of perspective obtained from hematological malignancies and non-Hodgkin's lymphoma.

Long-term outcomes of rituximab, temozolomide and high-dose methotrexate without consolidation therapy for lymphoma involving the CNS

Aim

To describe the long-term outcomes of patients with lymphoma in the CNS treated with rituximab, temozolomide and high-dose methotrexate without consolidation therapy.

Patients & methods

A retrospective cohort study of 46 consecutive patients with primary CNS lymphoma (PCNSL, 27 patients) or secondary CNS involvement of diffuse large B-cell lymphoma (DLBCL, 19 patients) who were treated with rituximab on day 1 in combination with high-dose methotrexate (days 1 and 15) and temozolomide (days 1-5) in 28-day cycles without further consolidation.

Results

Median follow-up was 21.2 months. Patients received a median of five cycles (range 1-15). Median overall survival (OS) was 26 months and median progression-free survival was 8.6 months. At 3 years, 37% of patients were alive and without evidence of disease. The patients with PCNSL had a significantly higher response rates (ORR 81 vs 47%; p = 0.015) and longer median OS (55.3 vs 4.8 months; p < 0.01) than those with secondary CNS DLBCL. Toxicities were mild and manageable.

Conclusion

The rituximab, temozolomide and methotrexate regimen is an effective therapy for patients with PCNSL without the toxicities typically associated with consolidation therapy.

Prognostic factors for primary central nervous system lymphomas treated with high-dose methotrexate-based chemo-radiotherapy

Background

Primary central nervous system lymphoma (PCNSL) remains an aggressive and refractory tumor despite high-dose methotrexate-based chemo-radiotherapy. Age and performance status have been shown to be important clinical prognostic factors, however others, especially molecular factors, affecting the prognosis are still uncertain.

Methods

We investigate clinical, neuroimaging and immunohistochemical data in tissue from 41 PCNSL patients treated primarily with methotrexate-based chemo-radiotherapy and evaluate the influence of potential prognostic factors on clinical outcome as well as correlation among these factors.

Results

Median progression-free survival (PFS) and overall survival (OS) were 29 and 73 months, respectively. Expression of the mismatch repair (MMR) proteins, MLH1, MSH2, MSH6 and PMS2, correlated tightly with each other and high expression of MSH2 was significantly associated with better OS and PFS (P = 0.005 and P = 0.007), while methotrexate metabolism-related proteins did not affect survival. In addition, low expression of PMS2 was an independent predictor of methotrexate resistance (P = 0.039). Among neuroimaging findings, involvement of the fornix and tegmentum/velum were significantly associated with poorer OS (P < 0.001 and P = 0.013) and PFS (P = 0.014 and P = 0.043, respectively). Germinal center B cell (GCB)-PCNSL subtype as opposed to non-GCB subtype, tended toward better survival. Regarding oncogenes, cMYC-positive cases showed unfavorable OS (P = 0.046). By multivariate analysis, MSH2 and involvement of the fornix were independent predictors for both OS and PFS, whereas tegmentum/velum location and cMYC expression were significantly associated with OS.

Conclusions

Although further studies are needed, these results suggest that MMR protein expression, as well as specific deep locations and cMYC expression, may be a novel prognostic and predictive markers for PCNSL.

Immunochemotherapy using rituximab (RTX) and high-dose methotrexate (HD-MTX): an evaluation of the addition of RTX to HD-MTX in recurrent primary central nervous system lymphoma (PCNSL)

Background

There is increasing evidence that MTX-based chemotherapy is superior to HD-MTX alone. Rituximab (RTX) is effective in a variety of B-cell lymphomas and may enter the brain. The purpose of this study is to evaluate the addition of RTX to HD-MTX in recurrent primary central nervous system lymphoma (PCNSL).

Methods

Patients diagnosed with recurrent PCNSL at our institution between 2004 and 2009 were treated with HD-MTX (3.5-5.5 g/m2) every 2 weeks. From 2010, RTX (375 mg/m2) was administered every 2 weeks along with HD-MTX.

Results

Fifteen recurrences in 10 patients were treated with HD-MTX alone (MTX group). Another 15 recurrences in 10 patients were treated with RTX and HD-MTX (RTX group). In 13 (86.6%) of the 15 recurrences in both groups the pre-planned chemotherapy cycles were completed. In the MTX group, 10/15 (66.6%) recurrences achieved a complete response (CR/CRu), 2/15 (13.3%) recurrences achieved a partial response (PR) and 3/15 (20%) recurrences had progressive disease (PD). In the RTX group, the CR/CRu, PR and PD rates were the same as that in the MTX group. The median time to tumor progression (mTTP) was 9.1 months (range, 1.4-120.9 months) in the MTX group and 7.8 months (range, 0.9-52.3 months) in the RTX group. We found no significant difference in mTTP (9.1 vs. 7.8 months, HR 1.02, 95% CI 0.48-2.18, P = 0.94) between the two groups. All treatment-related toxicities were manageable without any severe events.

Conclusions

The addition of RTX to HD-MTX may not be a promising strategy for recurrent PCNSL. A future study with a larger sample size, longer follow-up, or different RTX dosing/schedule is warranted.

Primary CNS Lymphoma

Primary CNS lymphoma (PCNSL) is a rare form of extranodal non-Hodgkin lymphoma that is typically confined to the brain, eyes, and cerebrospinal fluid without evidence of systemic spread. The prognosis of patients with PCNSL has improved during the last decades with the introduction of high-dose methotrexate. However, despite recent progress, results after treatment are durable in half of patients, and therapy can be associated with late neurotoxicity. PCNSL is an uncommon tumor, and only four randomized trials and one phase III trial have been completed so far, all in the first-line setting. To our knowledge, no randomized trial has been conducted for recurrent/refractory disease, leaving many questions unanswered about optimal first-line and salvage treatments. This review will give an overview of the presentation, evaluation, and treatment of immunocompetent patients with PCNSL.

Primary central nervous system lymphoma

Primary central nervous system lymphoma (PCNSL) is an extranodal non-Hodgkin lymphoma (NHL) confined to the brain, leptomeninges, eyes, or spinal cord. The majority of PCNSL cases occur in the immunocompetent host, the focus of this review. The prognosis of PCNSL is inferior to that of other NHL subtypes including other organ-specific subtypes of extranodal NHL. The 5- and 10-year survival proportions for PCNSL are 29.3% and 21.6%, respectively. The diagnosis and management of PCNSL differs from that of other primary brain cancers and NHL in other parts of the body.