Temozolomide and methotrexate for primary central nervous system lymphoma in the elderly

Primary central nervous system lymphoma (PCNSL) in older patients

INTRODUCTION

Primary central nervous system lymphoma (PCNSL) is a rare, chemo and radio-sensitive tumor limited to the central nervous system. The incidence of PCSNL increases notably in the elderly population which represented approximately half of the patients. The limit of 'elderly' population remained debated and nonuniform, including 60 years as a cutoff for brain radiotherapy, 65 years for autologous stem-cell transplantation, and 70 years for the last clinical trials. Current therapeutic options include first line treatment based on high-dose methotrexate based polychemotherapy, consolidation chemotherapy, and adapted autologous stem cell transplantation for highly selected patients. At relapse, single agent targeted therapies or salvage chemotherapy followed by intensive consolidation are promising therapeutic options. Nevertheless, improving management of elderly patients is an urgent medical need that currently remains unresolved.

OBJECTIVE

We will focus on elderly patients with PCNSL and their specificities including clinical presentations, available therapeutic options and adaptations to be made.

CONCLUSION

To improve survival, it will be necessary to personalized and adapt the treatments, to each patient and his comorbidities, to increase their effectiveness and limit their toxicity in this frail population. Finally, inclusion of these patients in clinical trials is one of the major challenges to significantly change PCNSL elderly patient prognosis.

Radiotherapy for newly diagnosed primary central nervous system lymphoma: role and perspective

Whole brain radiotherapy (WBRT) has long been a key treatment of newly diagnosed primary central nervous system lymphoma (PCNSL). In the 1990s, the addition of high dose Methotrexate-based induction chemotherapy (HD MTX-based CT) has enabled a drastic improvement in PCNSL patients outcome. However, combined treatment has led to radiation-induced delayed neurotoxicity, especially in older patients. Alternative treatment strategies have been assessed to improve the efficacy and neurotoxicity ratio. Nowadays, in the elderly patients WBRT is widely omitted or deferred, and in younger patients WBRT is challenged by high dose chemotherapy with autologous stem cell transplant (HCT-ASCT) for consolidation treatment after HD MTX-based CT. In this setting, this review is addressed to clinicians with the aim to summarize the role of WBRT in the treatment of newly diagnosed PCNSL and its perspectives.

Primary central nervous system lymphoma

Primary central nervous system lymphoma (PCNSL) is a diffuse large B cell lymphoma in which the brain, spinal cord, leptomeninges and/or eyes are exclusive sites of disease. Pathophysiology is incompletely understood, although a central role seems to comprise immunoglobulins binding to self-proteins expressed in the central nervous system (CNS) and alterations of genes involved in B cell receptor, Toll-like receptor and NF-κB signalling. Other factors such as T cells, macrophages or microglia, endothelial cells, chemokines, and interleukins, probably also have important roles. Clinical presentation varies depending on the involved regions of the CNS. Standard of care includes methotrexate-based polychemotherapy followed by age-tailored thiotepa-based conditioned autologous stem cell transplantation and, in patients unsuitable for such treatment, consolidation with whole-brain radiotherapy or single-drug maintenance. Personalized treatment, primary radiotherapy and only supportive care should be considered in unfit, frail patients. Despite available treatments, 15-25% of patients do not respond to chemotherapy and 25-50% relapse after initial response. Relapse rates are higher in older patients, although the prognosis of patients experiencing relapse is poor independent of age. Further research is needed to identify diagnostic biomarkers, treatments with higher efficacy and less neurotoxicity, strategies to improve the penetration of drugs into the CNS, and roles of other therapies such as immunotherapies and adoptive cell therapies.

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

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

Prognostic value of circulating lymphocyte subsets in primary central nervous system lymphoma

BACKGROUND

Immunity plays an important role in CNS-DLBCL development. CNS-DLBCL predictive factors need to be improved.

OBJECTIVE

To evaluate the predictive value of circulating lymphocyte subsets in PCNSL patients.

METHODS

We prospectively analyzed blood lymphocyte immunophenotyping (LIP) in newly CNS-DLBCL referred to our institution between December 2013 and January 2020. LIP analysis was performed before rituximab and chemotherapy administration. The clinical, radiological, histological, biological and treatment data were retrospectively collected.

RESULTS

Fifty-three patients were included with a median age of 69.7 (range 21.7-87.5). Median KPS was 60 (range 30-100). Thirty-three patients (64%) presented with one or several lymphopenias: 21 (40%), 24 (46%) and 9 (17%) NK, T and B lymphopenias respectively. Only 11 patients (21%) had normal LIP. Median CD4+/CD8+ ratio was 2.11 (range 0.54-9.11). This ratio was normal, low or high in 27%, 28% and 44% of patients respectively. The presence of steroids did not impact LIP results. Complete, partial responses, stable and progressive disease (PD) were observed in 24 (50%), 10 (21%), 4 (8%), and 10 (21%) patients respectively. CD4+/CD8+ ratio tended to be different between refractory (PD patients) and non-refractory patients (p = 0.077, ROC AUC: 0.684). Median progression-free survival (PFS) and overall survival (OS) were 14.7 (95%CI 6.5-22.9) and 43.2 (95%CI 21.6-64.9) months, respectively. In multivariate analyses, adjusted by KPS, a CD4+/CD8+ ratio > 1.97 was associated with poor PFS [p = 0.043, HR = 3.32 (1.02-4.88)] and tended to be associated with worse OS (p = 0.064).

CONCLUSION

LIP at baseline may predict refractory disease and exhibits a prognostic value in CNS-DLBCL patients.

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.

Nanomedicine Applications in Treatment of Primary Central Nervous System Lymphoma: Current State of the Art

Primary central nervous system lymphoma (PCNSL) is a rare but highly aggressive subtype of extra nodal non-Hodgkin lymphoma (NHL), which is confined in the central nervous system (CNS). Despite recent advancements in treatment options, the overall prognosis of PCNSL remains poor. Among many unfavorable factors affecting efficacy, inadequate drug delivery into the CNS is still the thorniest challenge. Blood-brain barrier (BBB) constitutes a significant impediment, restricting entry of most therapeutics to the brain. Nanotechnology has offered great promise for brain diseases, as various nano-based drug delivery systems (NDDSs) have been developed for delivery of theranostic agents in to the CNS. These drug delivery systems possess significant advantages, including good feasibility, reliable safety profile, excellent BBB penetration and potent antitumor effects. As for treatment of PCNSL, numerous well-developed BBB-crossing nano-based strategies can be applied with proper modifications and improvements. Some exquisitely designed NDDSs specific for PCNSL have shown great potential. In this review, we provide a summary on current status of diagnosis and treatment of PCNSL, followed by an overview of BBB-crossing strategies applied in management of PCNSL, both novel and wellestablished. Finally, challenges and future perspectives in this field are also discussed.

Primary Central Nervous System Lymphoma in Elderly Patients: Management and Perspectives

The management of elderly patients suffering from primary central nervous system (CNS) lymphoma, who represent a rapidly growing population, is challenging. Despite the advances made in PCNSL treatment, the prognosis in older patients remains unsatisfactory. The high risk of systemic and CNS toxicity induced by a high-dose chemotherapy regimen and radiation therapy, respectively, limits the use of consolidation phase treatments in elderly patients and contributes to the poor outcome of these patients. Here, we review the current treatment strategies and ongoing trials proposed for elderly PCNSL patients.

Primary Central Nervous System Lymphoma: Long-Term Treatment Outcomes and Cost-Analysis from a Retrospective Study of High-Dose Methotrexate Based Chemoimmunotherapy and Reduced Dose Radiation Therapy Approach

Standard treatment of primary central nervous system lymphoma (PCNSL) in countries with limited resources remains conventional chemotherapy, with or without whole brain radiotherapy (WBRT). To evaluate the treatment outcomes, prognostic factors and costs in patients with PCNSL treated with high-dose Methotrexate, vincristine and procarbazine, plus Rituximab (MVP-R) followed by consolidation with reduced dose (rd) WBRT and Cytarabine chemotherapy. We conducted an institutional audit of the first line treatment of patients with PCNSL, who were treated with MVP-R regimen, WBRT, or both between September 2011 and January 2020. Long term neuro-cognitive toxicity was recorded on follow up. The 5-year overall survival (OS) was the primary end point. Of 54 patients, 42 were evaluable [median age: 54 years (19-73 years)]. The commonest subtype was activated B-cell subtype (90%). At presentation, multiple and deep brain lesions were reported in 38 and 73% patients, respectively. Combined chemoimmunotherapy was given to 41 patients and WBRT to 29 patients. 27 patients (65%) achieved a complete response, and 22 received rdWBRT. 7 patients with partial response received conventional dose WBRT. Among tested prognostic factors, response to treatment was the single most significant determinant. At a median follow-up of 58 months, the 5-year progression free survival was 42%, and 5-year OS was 60%. The median direct hospital costs incurred by most patients for investigations and treatment were $1976.45 and $12,078.49, respectively. MVP-R is a well-tolerated regimen with substantial long term outcomes. Among all prognostic factors, response to therapy is the most significant.

High-dose chemotherapy and autologous stem cell transplant in elderly patients with primary CNS lymphoma: a pilot study

Age-adapted high-dose chemotherapy and autologous stem cell transplantation is safe and highly effective in elderly patients with PCNSL.

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

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

Challenges in the Treatment of Newly Diagnosed and Recurrent Primary Central Nervous System Lymphoma

Primary central nervous system lymphomas (PCNSLs) are rare cancers of the central nervous system (CNS) and are predominantly diffuse large B-cell lymphomas of the activated B-cell (ABC) subtype. They typically present in the sixth and seventh decade of life, with the highest incidence among patients aged >75 years. Although many different regimens have demonstrated efficacy in newly diagnosed and relapsed or refractory PCNSL, there have been few randomized prospective trials, and most recommendations and treatment decisions are based on single-arm phase II trials or even retrospective studies. High-dose methotrexate (HD-MTX; 3-8 g/m2) is the backbone of preferred standard induction regimens. Various effective regimens with different toxicity profiles can be considered that combine other chemotherapies and/or rituximab with HD-MTX, but there is currently no consensus for a single preferred regimen. There is controversy about the role of various consolidation therapies for patients who respond to HD-MTX-based induction therapy. For patients with relapsed or refractory PCNSL who previously experienced response to HD-MTX, repeat treatment with HD-MTX-based therapy can be considered depending on the timing of recurrence. Other more novel and less toxic regimens have been developed that show efficacy in recurrent disease, including ibrutinib, or lenalidomide ± rituximab. There is uniform agreement to delay or avoid whole-brain radiation therapy due to concerns for significant neurotoxicity if a reasonable systemic treatment option exists. This article aims to provide a clinically practical approach to PCNSL, including special considerations for older patients and those with impaired renal function. The benefits and risks of HD-MTX or high-dose chemotherapy with autologous stem cell transplantation versus other, better tolerated strategies are also discussed. In all settings, the preferred treatment is always enrollment in a clinical trial if one is available.

HDMTX-based polychemotherapy including intraventricular therapy in elderly patients with primary CNS lymphoma: a single center series

BACKGROUND

To investigate outcome and toxicity of high-dose systemic methotrexate (HDMTX)-based polychemotherapy and intracerebroventricular (ICV) chemotherapy via an Ommaya reservoir in elderly patients with primary central nervous system lymphoma (PCNSL).

METHODS

We performed a retrospective analysis on patients ⩾65 years with first diagnosis of PCNSL admitted to our center between January 2015 and December 2019. These patients were treated with a standardized chemotherapy protocol in case of absent contraindications for HDMTX-based chemotherapy. The protocol contained induction therapy with systemic rituximab, methotrexate and ifosfamide and consolidation treatment with systemic cytarabine (AraC) and ICV methotrexate, prednisolone and AraC.

RESULTS

Of a total of 46 patients seen in this period, 3 did not qualify for HDMTX. Thus, 43 patients were included in this analysis. Median age was 74 years (range 65-86), median Karnofsky performance score was 50 (range 20-90). Of the 43 patients, 32 (74.4%) completed treatment including ICV therapy. Complete remission/complete remission unconfirmed was achieved in 26 of 43 patients (60.5%), partial response (PR) in 3 (7%); 5 (11.6%) had progressive disease, and 3 (7.0%) died due to treatment-related complications; in the remaining 6 (14.0%) therapy could not be completed. Median progression free survival was 16 months (95% confidence interval 8-24 months) and median overall survival had not been reached after a median follow up of 23 months (range 1-52 months); the 75th percentile survival time was 12 months. No Ommaya reservoir infection was observed. Complications of ICV treatment were pericatheter leucencephalopathy in two patients and surgical scar dehiscence with cerebrospinal fluid leak in one patient.

CONCLUSION

Toxicity of HDMTX plus ICV chemotherapy for elderly patients with PCNSL was manageable and outcome was excellent for patients treated with this protocol.

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

This study aimed to define the maximum tolerated dose (MTD) of temozolomide (TMZ) concurrent with radiotherapy (RT) after high-dose methotrexate (HD-MTX) for newly diagnosed primary central nervous system lymphoma (PCNSL). Adult patients with PCNSL were treated according to a response-adapted strategy. HD-MTX (3.5 g/m²) was followed by concomitant RT and escalating TMZ (50-60-75 mg/m²/day, 5 days/week). The total radiation dose was modulated according to the patient's response to HD-MTX. All patients received 30 Gy to the whole brain plus leptomeninges to C2, including the third posterior of the orbital cavity (clinical target volume 2; CTV2), plus 6, 10, or 16 Gy to the primary site, including the residual mass (CTV1), if a complete response (CR), partial response (PR)/stable disease (SD), or progressive disease (PD) was observed, respectively. Acute toxicities were graded according to the RTOG-EORTC criteria. Dose-limiting toxicity (DLT) was defined as grade 4 hematological toxicity or grade 3-4 hepatic toxicity, although 75 mg/m²/day was the maximum dose regardless of DLT. Neurocognitive function was evaluated using the Mini-Mental State Examination. Three patients were enrolled at each TMZ dose level (total = 9 patients). Twelve lesions were treated. Six patients received 2 cycles of HD-MTX, while 3 received only 1 cycle because of hepatic or renal toxicity. All patients completed chemoradiotherapy without interruptions. No DLT events were recorded. TMZ appears to be tolerable at a dose of 75 mg/m²/day when administered concomitantly with radiotherapy and after HD-MTX.

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.

Overview of Dual-Acting Drug Methotrexate in Different Neurological Diseases, Autoimmune Pathologies and Cancers

Methotrexate, a structural analogue of folic acid, is one of the most effective and extensively used drugs for treating many kinds of cancer or severe and resistant forms of autoimmune diseases. In this paper, we take an overview of the present state of knowledge with regards to complex mechanisms of methotrexate action and its applications as immunosuppressive drug or chemotherapeutic agent in oncological combination therapy. In addition, the issue of the potential benefits of methotrexate in the development of neurological disorders in Alzheimer’s disease or myasthenia gravis will be discussed.

Temozolomide as a Single Agent Maintenance Therapy in Elderly Patients With Primary CNS Lymphoma

INTRODUCTION

Optimal management of elderly patients with primary central nervous system lymphoma (PCNSL) after induction therapy is unclear. Whole-brain radiotherapy and autologous stem cell transplantation carry increased toxicity in patients older than 60 years of age, which might outweigh the benefits in this group. Temozolomide (TMZ) has established antineoplastic activity in the central nervous system in other disease states, with a favorable toxicity profile.

PATIENTS AND METHODS

We report efficacy and tolerability in a series of 10 patients treated off-label with TMZ maintenance after completion of R-MPV (rituximab, methotrexate, procarbazine and vincristine) treatment for or primary diagnosed PCNSL.

RESULTS

Median progression-free survival (PFS) was 57 months, 2-year PFS was 67%, and 5-year PFS was 33%. Median overall survival (OS) was 63 months, 2-year OS was 88%, and 5-year OS was 57%. TMZ was generally well tolerated, with the most common toxicity of Grade 3 or higher being thrombocytopenia in 3 patients (30%).

CONCLUSION

These outcomes suggest that TMZ might have activity for maintenance in elderly patients with PCNSL, when more aggressive treatments are contraindicated.

High-dose Methotrexate plus temozolomide with or without rituximab in patients with untreated primary central nervous system lymphoma: A retrospective study from China

The purpose of this retrospective study was to compare the efficacy and toxicity of high-dose methotrexate plus temozolomide (MT regimen) and rituximab plus MT (RMT regimen) in patients with untreated primary central nervous system lymphoma (PCNSL). A total of 62 patients with untreated PCNSL were enrolled between January 2005 and December 2015, with the median age of 53.5 years (range 29-77).In this study, 32 patients received RMT as induction therapy, and 30 received MT. Objective responses were noted in 93.7% of the patients in the RMT group and in 69.0% of the patients in the MT group (P = 0.018), while complete responses were noted in 53.2% of the patients in the RMT group and 27.6% of the patients in the MT group (P < 0.001). The 2- and 5-year PFS rates were 81.3% and 53.3%, respectively, for the RMT group and 46.5% and 29.1%, respectively, for the MT group (P = 0.019). The 2- and 5-year overall survival (OS) rates were 82.3% and 82.3%, respectively, for the RMT group and 65.7% and 50.0%, respectively, for the MT group (P = 0.015). Multivariate analyses showed that therapeutic regimen (RMT vs MT) was an independent prognostic factor for PFS and OS. Our encouraging results suggest that the RMT regimen may be a feasible and safe therapeutic approach for first-line treatment of PCNSL.

Primary CNS Lymphoma in the Elderly: The Challenge

Primary central nervous system (CNS) lymphoma is an aggressive brain tumor sensitive to chemotherapy and radiotherapy. Its incidence has increased in the elderly, and they account for the majority of patients. The median survival of patients older than 70 years did not change over the last 40 years and remained in the range of 6-7 months. The definition of elderly is nonuniform, and chronological age is not the best marker of treatment tolerability or a predictor of treatment-related toxicity. Some patients who are fit can tolerate induction, consolidation, and even high-dose chemotherapy with autologous stem cell transplantation, whereas others who have multiple comorbidities with reduced renal and bone marrow function can tolerate only intermediate doses of methotrexate. The latter may benefit from maintenance treatment. The "elderly" are also susceptible to the accelerated and detrimental cognitive side effects of whole-brain irradiation which is an alternative consolidation to high-dose chemotherapy. The optimal treatment remains an unresolved matter. A comprehensive comorbidity and geriatric assessment is imperative for appraisal of treatment-induced risks for CNS and systemic toxicity. An individualized approach is required aiming to prolong survival while minimizing toxicity. Future studies should assess the potential of new agents for improving outcome and maintaining quality of life.

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.

Diffuse large B-cell lymphoma of the central nervous system presenting as "lymphomatosis cerebri" and dementia in elderly man: Case report and review of the literature

RATIONALE

Lymphomatosis cerebri is a rare form of PCNSL, characterized by diffuse infiltration of lymphoma cells in cerebral parenchyma, without mass-formation and mild or no contrast enhancement on magnetic resonance (MR) imaging. There are less than 50 cases described in the literature under the term Lymphomatosis cerebri.

PATIENT CONCERNS

A 74-year-old man presented to our service with progressive dementia for 12 months and accelerated cognitive decline within the last two months. Brain magnetic resonance imaging showed areas of hyperintensity involving predominantly the white matter of frontal lobes and knee of the corpus callosum, along with areas of blood-brain barrier disruption and areas of restricted diffusion. Stereotaxy brain surgery was indicated into contrasting areas and histologically there was heterogeneous foci of discreet infiltration of rare medium-large lymphoid cells intermingled with inflammatory cells and these atypical lymphoid cells were placed on breakdown neuropil and did not form tumor mass or sheets of cells, but occasionally displayed perivascular distribution. Immunohistochemically, these atypical lymphoid cells expressed CD20, Bcl2, Bcl6 and, heterogeneously, IRF4/MUM1.

DIAGNOSIS

The diagnosis of a primary CNS diffuse large B-cell lymphoma manifested as lymphomatosis cerebri was performed.

INTERVENTIONS

The treatment of choice was: temozolomide 100 mg/m (D1 to D5), methotrexate 3 g/m (D1, D10, and D20) and rituximab 375 mg/m.

OUTCOMES

The patient evolved with progressive neurological deterioration, regardless of the improvement on neuroimaging.

LESSONS

We described the diagnostic dilemma we faced with an elderly man with rapid cognitive impairment and a myriad of differential diagnoses, diagnosed with primary CNS diffuse large B-cell lymphoma with a lymphomatosis cerebri-like pattern.

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.

Characteristics and Outcomes of Primary Central Nervous System Lymphoma: A Retrospective Study of 91 Cases in a Chinese Population

BACKGROUND

Primary central nervous system lymphoma (PCNSL) is a rare disease affecting the brain, leptomeninges, spinal cord, cerebrospinal fluid, or vitreoretinal compartment, without evidence of systemic disease. Prognosis is still poor after intensive methotrexate-based chemotherapy.

METHODS

Clinical data of 91 patients treated in a tertiary referral center during a 13-year period were retrospectively reviewed.

RESULTS

The estimated median progression-free survival and overall survival (OS) for the entire cohort were 39.1 months (95% confidence interval [CI], 14.1-64.0 months) and 54.5 months (95% CI, 28.9-80.1 months), respectively. Estimated 5-year progression-free survival and OS were 37.0% ± 6.5% and 47.5% ± 7.5%. Survival was associated with cycles of methotrexate only in multivariate analysis. Seventy-four patients received methotrexate-based chemotherapy after diagnosis. Thirty-nine patients experienced disease progression. Patients with relapsed/refractory disease had a poor survival, with median second OS (calculated from the date of first disease progression to the time of death from any cause) being 7.2 months (95% CI, 2.5-12.00 months). Three patients responded to ibrutinib after disease progression and incurred no fungal infection.

CONCLUSIONS

The outcomes of patients with PCNSL treated in our cohort are still poor. Relapse or refractory PCNSL and those not tolerating aggressive chemotherapy urgently require new approaches to improve their still dismal prognosis. Novel agents such as ibrutinib have shown promising clinical activity. Future studies should focus on the predictive biomarkers for the treatment of PCNSL with novel agents to provide precision medicine for PCNSL.

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.

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.

Primary central nervous system lymphoma: Retrospective analysis of 34 cases in a single centre

Objective

To retrospectively analyse outcomes in patients with primary central nervous system lymphoma (PCNSL), which is a malignant CNS non-Hodgkin’s lymphoma with a poor prognosis.

Methods

This study retrospectively analysed the treatment and outcomes of patients with PCNSL, which were divided into two groups: surgery (S) group and surgery/biopsy+chemotherapy (SC) group. The latter group was further subdivided into four cohorts based on the treatment regimen: cyclophosphamide, epidoxorubicin, vincristine and prednisone (CHOP), high-dose methotrexate (HDM)+dexamethasone+rituximab (HDM+D+R), HDM+D+temozolomide (HDM+D+T), and HDM+D+R+T.

Results

The study enrolled 34 patients; 10 of which received surgery only. Between the S and SC groups, the median progression-free survival (PFS) and overall survival (OS) of intracranial PCNSLs (n = 32) were 8.5 months versus 29 months, respectively; and 8.5 months versus 54 months, respectively (5-year OS: 10.0% versus 48.7%, respectively; 2-year PFS: 0.0% versus 52.6%, respectively). Comparing the CHOP and HDM-based chemotherapy cohorts, the median PFS and OS were 15 months versus not achieved, respectively, and 25 months versus not achieved, respectively (5-year OS: 20.0% versus 60.8%, respectively; 2-year PFS: 20.0% versus 62.7%, respectively).

Conclusion

Chemotherapy appears to provide a better OS and PFS for patients with PCNSLs compared with surgery alone. HDM+D+T and HDM+D+R+T may be effective choices for PCNSL treatment.

Advances in the treatment of newly diagnosed primary central nervous system lymphomas

Primary central nervous system lymphoma (PCNSL) is a type of highly invasive non-Hodgkin lymphoma. With a growing number of organ transplantation and immunosuppressant therapy, the incidence of PCNSL has been growing rapidly in recent years, which is attributed to the increased incidence of HIV/AIDS, a prominent risk factor for developing PCNSL. The rising rate of PCNSL incidence is the highest among the intracranial tumors. In the past 20 years, dozens of clinical trials related to PCNSL have been registered, but adequate therapeutics are still challenging. Currently, the chemotherapy regimens based on high-dose methotrexate and whole-brain radiotherapy are the two main therapeutic options; however, the toxicity associated with those is the main problem that challenges medical researchers. Novel agents and therapeutic strategies have been developed in recent years. In the current review, we describe advances in the treatment of PCNSL and discuss novel therapeutic approaches currently in development, such as the use of rituximab, disruption of the blood-brain barrier, and state-of-the-art radiotherapy.

Pemetrexed for primary central nervous system lymphoma in the elderly

OBJECTIVE

The aim of this study was to evaluate the efficacy and safety of a consecutive series of elderly patients with primary central nervous system lymphoma (PCNSL) treated with single-agent pemetrexed without radiotherapy or intrathecal chemotherapy.

METHODS

Twelve histologically confirmed newly diagnosed PCNSL patients older than 65 years were studied between 2008 and 2013. An induction chemotherapy was initially given (pemetrexed 600 mg/m(2) on day 1, every 3 weeks). Patients achieving a complete, partial response or stable disease proceeded to a maintenance phase (up to 6 cycles). Patients with progressive/recurrent disease (PD) were treated with whole brain radiotherapy on an individual basis.

RESULTS

Four patients presented complete response, six patients showed partial response and two patients presented progressive disease. The median progression-free survival (PFS) was 9.0 months [95 % confidence interval (CI) 2.0-45.3] and the median overall survival was 19.5 months (95 % CI 5.0-45.3). Adverse events included leukocytopenia, anemia, fatigue, rash and vomiting. No neurotoxicity or treatment-related death was observed. The estimated 1-year and 2-year survival rate was 66.7 and 41.7 %, respectively.

CONCLUSIONS

Our efficacy results demonstrate that the single-agent pemetrexed was feasible, active and well tolerated in elderly patients with PCNSL. Furthermore, this single-agent regimen results in higher response rates and less toxicity comparable with other chemotherapy or radiotherapy regimens. Prospectively, controlled studies are warranted to confirm such results.

Methotrexate and temozolomide versus methotrexate, procarbazine, vincristine, and cytarabine for primary CNS lymphoma in an elderly population: an intergroup ANOCEF-GOELAMS randomised phase 2 trial

BACKGROUND

No standard chemotherapy regimen exists for primary CNS lymphoma, reflecting an absence of randomised studies. We prospectively tested two promising methotrexate-based regimens, one more intensive and a milder regimen, for primary CNS lymphoma in the elderly population, who account for most patients.

METHODS

In this open-label, randomised phase 2 trial, done in 13 French institutions, we enrolled immunocompetent patients who had neuroimaging and histologically confirmed newly diagnosed primary CNS lymphoma, were aged 60 years and older, and had a Karnofsky performance scale score of 40 or more. Participants were stratified by Karnofsky performance scale score (<60 vs ≥60) and treating institution and randomly assigned (1:1) to receive methotrexate (3·5 g/m(2)) with temozolomide (150 mg/m(2)) or methotrexate (3·5 g/m(2)), procarbazine (100 mg/m(2)), vincristine (1·4 mg/m(2)), and cytarabine (3 mg/m(2)). Neither regimen included radiotherapy; both included prophylactic G-CSF and corticosteroids. The primary endpoint was 1-year progression-free survival. Analysis was intent to treat, in a non-comparative phase 2 trial design. This study is registered with ClinicalTrials.gov, number NCT00503594.

FINDINGS

Between July 16, 2007, and March 25, 2010, 98 patients were enrolled, of whom 95 were randomly assigned and analysed; 48 to methotrexate with temozolomide and 47 to methotrexate, procarbazine, vincristine, and cytarabine. 1-year progression-free survival was 36% (95% CI 22-50) in the methotrexate, procarbazine, vincristine, and cytarabine group and 36% (22-50) in the methotrexate with temozolomide group; median progression-free survival was 9·5 months (95% CI 5·3-13·8) versus 6·1 months (3·8-11·9), respectively. Objective responses were noted in 82% (95% CI 68-92) of patients in the methotrexate, procarbazine, vincristine, and cytarabine group versus 71% (55-84) of patients in the methotrexate with temozolomide group. Median overall survival was 31 months (95% CI 12·2-35·8) in the methotrexate, procarbazine, vincristine, and cytarabine group and 14 months (8·1-28·4) in the methotrexate with temozolomide group. No differences were noted in toxic effects between the two groups. The most common grades 3 and 4 toxicities in both groups were liver dysfunction (21 [4%] in the the methotrexate and temozolomide group and 18 [38%] in the methotrexate, procarbazine, vincristine, and cytarabine group), lymphopenia (14 [29%] and 14 [30%]), and infection (six [13%] and seven [15%]). To date, 33 (69%) patients in the methotrexate and temozolomide group have died, versus 31 (55%) in the methotrexate, procarbazine, vincristine and cytarabine group. Quality-of-life evaluation (QLQ-C30 and BN20) showed improvements in most domains (p=0·01-0·0001) compared with baseline in both groups. Prospective neuropsychological testing showed no evidence of late neurotoxicity.

INTERPRETATION

In this study of two different methotrexate-based combination regimens in elderly patients, the efficacy endpoints tended to favour the methotrexate, procarbazine, vincristine, and cytarabine group. Both regimens were associated with similar, moderate toxicity, but quality of life improved with time, suggesting pursuing treatment in these poor prognosis patients is worthwhile. New alternatives are needed to improve response duration in this population.

FUNDING

Schering-Plough/Merck and French Government.

First-line treatment and outcome of elderly patients with primary central nervous system lymphoma (PCNSL)--a systematic review and individual patient data meta-analysis

BACKGROUND

To investigate prognosis and effects of first-line therapy in elderly primary central nervous system lymphoma (PCNSL) patients.

PATIENTS AND METHODS

A systematic review of studies about first-line therapy in immunocompetent patients ≥60 years with PCNSL until 2014 and a meta-analysis of individual patient data from eligible studies and international collaborators were carried out.

RESULTS

We identified 20 eligible studies; from 13 studies, we obtained individual data of 405 patients, which were pooled with data of 378 additional patients (N = 783). Median age and Karnofsky Performance Score (KPS) was 68 years (range: 60-90 years) and 60% (range: 10%-100%), respectively. Treatments varied greatly, 573 (73%) patients received high-dose methotrexate (HD-MTX)-based therapy. A total of 276 patients received whole-brain radiotherapy (median 36 Gy, range 28.5-70 Gy). KPS ≥ 70% was the strongest prognostic factor for mortality [hazard ratio (HR) 0.50, 95% confidence interval (CI) 0.41-0.62]. After a median follow-up of 40 months, HD-MTX-based therapy was associated with improved survival (HR 0.70, 95% CI 0.53-0.93). There was no difference between HD-MTX plus oral chemotherapy and more aggressive HD-MTX-based therapies (HR 1.39, 95% CI 0.90-2.15). Radiotherapy was associated with an improved survival, but correlated with an increased risk for neurological side-effects (odds ratio 5.23, 95% CI 2.33-11.74).

CONCLUSIONS

Elderly PCNSL patients benefit from HD-MTX-based therapy, especially if combined with oral alkylating agents. More aggressive HD-MTX protocols do not seem to improve outcome. WBRT may improve outcome, but is associated with increased risk for neurological side-effects. Prospective trials for elderly PCNSL patients are warranted.

Successful change of treatment strategy in elderly patients with primary central nervous system lymphoma by de-escalating induction and introducing temozolomide maintenance: results from a phase II study by the Nordic Lymphoma Group

The Nordic Lymphoma Group has conducted a phase ll trial in newly diagnosed primary central nervous system lymphoma patients applying an age-adjusted multi-agent immunochemotherapy regimen, which in elderly patients included temozolomide maintenance treatment. Patients aged 18-75 years were eligible. Thirty-nine patients aged 18-65 years and 27 patients aged 66-75 years were enrolled. The median age of the two age groups was 55 and 70 years, respectively. The overall response rate was 73.8% for the entire cohort: 69.9% in the younger and 80.8% in the elderly subgroup. With a median follow up of 22 months, the 2-year overall survival probability was 60.7% in patients aged 65 years or under and 55.6% in patients aged over 65 years (P=0.40). The estimated progression-free survival at two years was 33.1% (95%CI: 19.1%-47.9%) in patients aged under 65 years and 44.4% (95%CI: 25.6%-61.8%) in the elderly subgroup (P=0.74). Median duration of response was ten months in the younger subgroup, and not reached in the elderly patient subgroup (P=0.33). Four patients aged 64-75 years (6%) died from treatment-related complications. Survival in the two age groups was similar despite a de-escalation of induction treatment in patients aged over 65 years. Duration of response in elderly patients receiving maintenance temozolomide was longer than in the younger age subgroup. While toxicity during induction is still of concern, especially in the elderly patients, we conclude from these data that de-escalation of induction therapy in elderly primary central nervous system lymphoma patients followed by maintenance treatment seems to be a promising treatment strategy. (clinicaltrials.gov identifier:01458730).

A phase 1 dose escalation study of idarubicin combined with methotrexate, vindesine, and prednisolone for untreated elderly patients with primary central nervous system lymphoma. The GOELAMS LCP 99 trial

Treatment of primary central nervous system lymphoma (PCNSL) in elderly patients remains unsatisfactory. To develop a new high-dose methotrexate (HD-MTX)-based regimen including idarubicin, a phase 1 multicenter dose escalation study was conducted to determine the maximum-tolerated dose (MTD) of idarubicin. Thirty-five immunocompetent patients with PCNSL were enrolled. The median age was 65 years (range, 60-70 years). MTX and vindesine (VDS) were given at the fixed dose of 3 g/m(2) (6-hr intravenous [IV]) and 3 mg/m(2) IV on day 1, respectively. Prednisolone (PRED) was given at the fixed dose of 60 mg/m(2) (IV or orally) on days 1-5. Idarubicin was escalated in increments of 2 mg/m(2) with doses ranging from 12-18 mg/m(2) IV on day 1. Treatment was repeated three times every 3 weeks. Dose-limiting toxicity (DLT) was defined as grade 4 neutropenia for more than 7 days, thrombocytopenia grade 4 or nonhaematological toxicity more than grade 2. The MTD of idarubicin was reached at 16 mg/m(2) . At this level, the main haematological toxicities were thrombocytopenia grade 4: 5% and neutropenia grade 3 or 4 (52%); the main nonhaematological toxicities were grade 3 or 4 infectious disease (5%) and grade 2 renal failure (9%). For the study population, median overall and progression-free survival were 19 and 13 months, respectively. Our study suggests that the MTD of idarubicin in combination with HD-MTX, VDS, and PRED, should be 16 mg/m(2) . Further studies will be necessary to challenge a standard treatment in elderly patients with PCNSL.

MGMT promoter methylation and correlation with protein expression in primary central nervous system lymphoma

The O (6)-methylguanine-DNA-methyltransferase (MGMT) gene encodes for a DNA repairing enzyme of which silencing by promoter methylation is involved in brain tumorigenesis. MGMT promoter methylation represents a favorable prognostic factor and has been associated with a better response to alkylating agents in glioma and systemic lymphoma. Primary central nervous system lymphoma (PCNSL) is a rare and aggressive extranodal malignant lymphoma. The current standard of care, based on high-dose methotrexate chemotherapy, has improved prognosis but outcome remains poor for a majority of patients. Therapeutic progress in this field is conditioned by limited biological and molecular knowledge about the disease. Temozolomide has recently emerged as an alternative option for PCNSL treatment. We aimed to analyze the MGMT gene methylation status in a series of 24 PCNSLs, to investigate the relationship between methylation status of the gene and immunohistochemical expression of MGMT protein and to evaluate the possible prognostic significance of these biomarkers. Our results confirm that methylation of the MGMT gene and loss of MGMT protein are frequent events in these lymphomas (54 % of our cases) and suggest that they are gender and age related. MGMT methylation showed high correlation with loss of protein expression (concordance correlation coefficient = -0.49; Fisher exact test: p < 0.01), different from what has been observed in other brain tumors. In the subgroup of ten patients who received high dose chemotherapy, the presence of methylated MGMT promoter (n = 4), seems to be associated with a prolonged overall survival (>60 months in three of four patients). The prognostic significance of these molecular markers in PCNSL needs to be further studied in groups of patients treated in a homogeneous way.

Expression of G protein-coupled estrogen receptor in irritable bowel syndrome and its clinical significance

OBJECTIVES

Estrogen is suggested to participate in pathogenesis of irritable bowel syndrome (IBS), but expression of G protein-coupled estrogen receptor (GPER) in the colon of IBS patients has never been investigated. The aim of this study was to investigate the expression of GPER and classical estrogen receptors in the colon of IBS patients and healthy controls.

METHODS

Colonic biopsies were obtained by endoscopy from patients with IBS (n=46) and healthy subjects (n=13). Expression of GPER, estrogen receptor α (ERα) and estrogen receptor β (ERβ) in mast cells were measured by double-labelling immunofluorescence. Quantification of mRNA expression was performed for GPER, ERα and ERβ by real-time polymerase chain reaction.

RESULTS

Differential distribution of GPER, ERα and ERβ were detected in human colonic mucosa. The expression of GPER in the cytoplasm of mast cells and GPER-positive cells was significantly higher in diarrhea-predominant IBS (D-IBS) patients than that in constipation-predominant IBS (C-IBS, P<0.001) patients and healthy subjects (P=0.005). ERα and ERβ were not detected in majority of mast cells in colonic mucosa and no difference of immunostaining results for ERα and ERβ was found among these three groups. A positive correlation (r=0.451, P=0.011) between GPER-positive cell counts and abdominal pain severity was observed in D-IBS group. Relative mRNA expression of GPER in D-IBS was also higher than that in C-IBS (P=0.018) and healthy subjects (P=0.011).

CONCLUSIONS

The present study, for the first time, demonstrated the expression of GPER in human colonic mucosa and its correlation with abdominal pain severity.

Clinical outcomes of patients with newly diagnosed primary central nervous system lymphoma are comparable on treatment with high-dose methotrexate plus temozolomide and with high-dose methotrexate plus cytarabine: a single-institution experience

The role of temozolomide in untreated PCNSL patients has not yet been clearly defined. The purpose of this study was to compare the efficacy and toxicity of MT and MC chemotherapy in this population. A total of 41 consecutive patients were enrolled from March 2001 to July 2011. The ORR and CRR for MT vs. MC were 70% vs. 61.9% and 45% vs. 38.1% on ITT basis, (p = NS); 73.7% vs. 68.4% and 47.4% vs. 42.1% on PP basis, respectively (p = NS). Grade 3-4 hematological toxicities were more common in MC than in MT group (85.7% vs. 15%, p = 0.0001). One treatment-related death was observed in each group. The 5-year PFS and OS of MT (36% and 62.2%) were comparable to MC (32.6% and 46.7%), (p = NS). In summary, our preliminary results suggest that MT combination may be a simplified and effective regimen comparable to MC for newly diagnosed PCNSL.

Recent advances in treatment of primary central nervous system lymphoma

OPINION STATEMENT

Therapeutic options are limited in primary central nervous system lymphoma (PCNSL) with no uniform consensus on optimal management and few published, randomized trials. High-dose methotrexate in combination with other chemotherapeutic agents forms the mainstay of treatment. There hasn't been much progress beyond high-dose methotrexate in this disease, and although results from trials using high-dose chemotherapy and autologous stem-cell transplant seem promising, these need to be further validated. Moreover, the role of whole brain radiation in the upfront setting remains to be determined. However, international efforts in this direction are underway, with ongoing randomized trials in newly diagnosed PCNSL, more research on the molecular pathogenesis and biomarkers, and the use of novel agents in salvage therapy. There also is emphasis on quality of life parameters and neurocognitive status. Future treatment options should optimize high-efficacy rates while minimizing the risk of neurotoxicity.

Advantages of dose-dense methotrexate protocol for primary central nervous system lymphoma: comparison of two different protocols at a single institution

The efficacy and toxicity of high-dose methotrexate (HD-MTX)-based chemotherapy were retrospectively reviewed in patients with primary central nervous system lymphoma (PCNSL). All immunocompetent patients with histologically or radiographically diagnosed PCNSL treated between 2006 and 2012 at Niigata University Hospital were enrolled. Thirty-eight patients with a diagnosis of PCNSL were treated with one of two regimens during different time periods. During the first period, from 2006 to 2009, three 3-week cycles of MPV (MTX + procarbazine + vincristine) were administered (MPV3 group). In the second period, from 2010 to 2012, five 2-week cycles of MTX were administered (MTX5 group). High-dose cytarabine was used in both groups following HD-MTX-based chemotherapy. Whole-brain radiotherapy was used for patients who did not attain a complete response (CR) based on magnetic resonance images. In the MPV3 group, 20 out of 23 patients (87%) completed the planned treatment. The CR rate after chemotherapy was 30%, and 57% after radiation therapy. Thirteen out of 15 patients (87%) in the MTX5 group completed the planned treatment. The CR rates after chemotherapy and radiation therapy were 53% and 93%, respectively. Renal dysfunction was assessed by measuring creatinine clearance rates, which were very similar in both groups. In terms of hematologic toxicity and other adverse reactions, there was no significant difference between the two groups. In conclusion, dose-dense MTX chemotherapy improved outcome with acceptable toxicity compared with the treatment schedule for three cycles of MPV treatment.

Rituximab, methotrexate, procarbazine, and vincristine followed by consolidation reduced-dose whole-brain radiotherapy and cytarabine in newly diagnosed primary CNS lymphoma: final results and long-term outcome

PURPOSE

A multicenter phase II study was conducted to assess the efficacy of rituximab, methotrexate, procarbazine, and vincristine (R-MPV) followed by consolidation reduced-dose whole-brain radiotherapy (rdWBRT) and cytarabine in primary CNS lymphoma.

PATIENTS AND METHODS

Patients received induction chemotherapy with R-MPV (five to seven cycles); those achieving a complete response (CR) received rdWBRT (23.4 Gy), and otherwise, standard WBRT was offered (45 Gy). Consolidation cytarabine was given after the radiotherapy. The primary end point was 2-year progression-free survival (PFS) in patients receiving rdWBRT. Exploratory end points included prospective neuropsychological evaluation, analysis of magnetic resonance imaging (MRI) white matter changes using the Fazekas scale, and evaluation of the apparent diffusion coefficient (ADC) as a prognostic factor.

RESULTS

Fifty-two patients were enrolled, with median age of 60 years (range, 30 to 79 years) and median Karnofsky performance score of 70 (range, 50 to 100). Thirty-one patients (60%) achieved a CR after R-MPV and received rdWBRT. The 2-year PFS for this group was 77%; median PFS was 7.7 years. Median overall survival (OS) was not reached (median follow-up for survivors, 5.9 years); 3-year OS was 87%. The overall (N = 52) median PFS was 3.3 years, and median OS was 6.6 years. Cognitive assessment showed improvement in executive function (P < .01) and verbal memory (P < .05) after chemotherapy, and follow-up scores remained relatively stable across the various domains (n = 12). All examined MRIs (n = 28) displayed a Fazekas score of ≤ 3, and no patient developed scores of 4 to 5; differences in ADC values did not predict response (P = .15), PFS (P = .27), or OS (P = .33).

CONCLUSION

R-MPV combined with consolidation rdWBRT and cytarabine is associated with high response rates, long-term disease control, and minimal neurotoxicity.

Primary central nervous system lymphoma: what a neurologist/neurosurgeon should know?

Primary central nervous system lymphoma is a rare disease, with bad prognosis. Neurologists and neurosurgeons should be familiar with the diagnostic,and biologic features, as well as the initial management of patients. A correct approach to these patients is mandatory for a better outcome.

High-dose methotrexate, high-dose cytarabine and temozolomide for the treatment of primary central nervous system lymphoma (PCNSL)

Treatment of primary central nervous system lymphoma (PCNSL) associates with low response rates and poor survival using conventional radio and chemotherapy. Due to its favorable toxicity profile, temozolomide has emerged as a new option for treatment of PCNSL in young patients. In this study, we report a series of PCNSL patients treated with an innovative regimen combining high dose of both cytarabine and methotrexate with temozolomide without radiotherapy or intrathecal chemotherapy. To evaluate a new intensive chemotherapy with temozolomide, trying to assess response and progression-free survival rates and if the results are promising, we are aiming at evaluating the overall survival (OS) taking into consideration the toxicity profile. The study was performed at Al Mowassa Charity Hospital in Damascus (Syria). Forty patients with histologically confirmed PCNSL median age 52 years (range 20-65) years were included. Biopsies were cultured, and a karyotyping was made in 32 patients. An induction chemotherapy was started, and methotrexate 3 gr/m² over 12 h on day 1, cytarabine 3 gr/m² every 12 h on day 1 and temozolomide 150 mg/m² from day 2 through day 6 with a total of 6 cycles were given on a monthly basis. Among the 40 patients included in the study, a complete response was observed in 34 patients (85%) and a partial response in the remaining 6 patients (15%). Disease progressed in 8 out of 40 patients (20%) while 32 patients are still living at 5 years making the OS reaching 77%. Grade II nephrotoxicity was observed in 2 patients while grade III and IV hematotoxicity was observed in 5 patients. High dose of both Ara-C and MTX combined with temozolomide appears to be a good choice in the treatment of PCNSL, in the light of good response and OS rates, taking into consideration the acceptable toxicity profile. However, a larger trial is needed to make it an acceptable new combination as a first line for PCNSL patients.

O6-methylguanine-DNA methyltransferase (MGMT) immunohistochemistry as a predictor of resistance to temozolomide in primary CNS lymphoma

Temozolomide, an alkylating agent, has shown promise in treating primary central nervous system lymphoma (PCNSL). The enzyme O(6)-methylguanine-DNA methyltransferase (MGMT) repairs alkylating damage, such as that induced by temozolomide. We hypothesized that MGMT immunohistochemistry would predict resistance to temozolomide in PCNSL. A retrospective study of newly-diagnosed and recurrent PCNSL patients treated at our institution was conducted to study the predictive value of MGMT immunohistochemistry for response to temozolomide. 20 patients who were treated with temozolomide as a single agent were identified during the study time period. 6/20 patients demonstrated a response, corresponding to an objective response rate of 30 % (95 % CI 8-52). Five patients with low MGMT level (<30 %) showed a response to temozolomide. Only one of 10 patients (10 %) with high MGMT level (≥30 %) exhibited a response to temozolomide. Small sample numbers precluded formal statistical comparisons. Two patients with complete response remain alive without progressive disease 6.7 and 7.2 years after temozolomide initiation. Immunohistochemistry can be performed on small biopsies to selectively assess MGMT status in tumor versus surrounding inflammation. MGMT analysis by immunohistochemistry may predict response to temozolomide in PCNSL and should be prospectively investigated.