PRIMARY CENTRAL NERVOUS SYSTEM LYMPHOMAS

Primary central nervous system lymphoma (PCNSL) is a rare and aggressive extranodal non-Hodgkin lymphoma (NHL) that is confined to the brain, eyes, spinal cord, or leptomeninges without systemic involvement. The overall prognosis, diagnosis, and management of PCNSL differ from those for other types of NHL. Prompt diagnosis and initiation of treatment are vital for improving clinical outcomes. PCNSL is responsive to radiation therapy; however, whole-brain radiotherapy (WBRT) inadequately controls the disease when it is used alone, and its delayed neurotoxicity causes neurocognitive impairment, especially in elderly patients. High-dose methotrexate (HD-MTX)-based induction chemotherapy with or without autologous stem cell transplantation (ASCT) or reduced-dose WBRT leads to durable disease control and less neurotoxicity. The optimal treatment has yet to be defined; however, HD-MTX-based induction chemotherapy is considered standard for newly diagnosed PCNSL. Ongoing randomized trials are addressing the roles of rituximab and consolidative treatment with ASCT or reduced-dose WBRT. Despite high tumor response rates with the initial treatment, many patients relapse with a very poor prognosis. The optimal treatment for refractory or relapsed PCNSL is poorly defined. The choice of salvage treatment depends on a patient's age, previous treatment and response, performance status, and comorbidities at the time of relapse. This review provides an overview of the clinical features, diagnosis, pathology, and management of PCNSL in immunocompetent patients, and it focuses on recent advances in treatment. Cancer 2017;123:4314-24. © 2017 American Cancer Society.

High-dose chemotherapy followed by autologous hematopoietic stem cell transplantation (HDT-ASCT) is listed as a consolidation therapy option for primary central nervous system (CNS) lymphoma in the guidelines of western countries. The advantages of HDT-ASCT for primary CNS lymphoma as consolidation are believed to be high rates of long-term remission and lower neurotoxicity, even though its eligibility is limited to younger fit patients. In the Japanese guideline, HDT-ASCT for primary CNS lymphoma is however not recommended in daily practice, mainly because thiotepa was unavailable since 2011. The Japanese registry data for hematopoietic transplantation have shown that primary CNS lymphoma patients were treated with various HDT regimens and thiotepa-containing HDT was associated with better progression free survival (P=.019), lower relapse (P=.042) and a trend toward a survival benefit (Kondo E et al, Biol Blood Marrow Transplant 2019). A pharmacokinetic study of thiotepa(DSP-1958) in HDT-ASCT for lymphoma was conducted in 2017, and thiotepa was approved for HDT-ASCT in lymphoma this March, meaning that optimal HDT regimen for CNS lymphoma is now available in Japan. The treatment strategy of CNS lymphoma needs further development to improve survival and reduce toxicity.

<div>Abstract<p>Primary central nervous system lymphoma (PCNSL) is an isolated type of lymphoma of the central nervous system and has a dismal prognosis despite intensive chemotherapy. Recent genomic analyses have identified highly recurrent mutations of MYD88 and CD79B in immunocompetent PCNSL, whereas LMP1 activation is commonly observed in Epstein–Barr virus (EBV)-positive PCNSL. However, a lack of clinically representative preclinical models has hampered our understanding of the pathogenic mechanisms by which genetic aberrations drive PCNSL disease phenotypes. Here, we establish a panel of 12 orthotopic, patient-derived xenograft (PDX) models from both immunocompetent and EBV-positive PCNSL and secondary CNSL biopsy specimens. PDXs faithfully retained their phenotypic, metabolic, and genetic features, with 100% concordance of MYD88 and CD79B mutations present in PCNSL in immunocompetent patients. These models revealed a convergent functional dependency upon a deregulated RelA/p65-hexokinase 2 signaling axis, codriven by either mutated MYD88/CD79B or LMP1 with Pin1 overactivation in immunocompetent PCNSL and EBV-positive PCNSL, respectively. Notably, distinct molecular alterations used by immunocompetent and EBV-positive PCNSL converged to deregulate RelA/p65 expression and to drive glycolysis, which is critical for intracerebral tumor progression and FDG-PET imaging characteristics. Genetic and pharmacologic inhibition of this key signaling axis potently suppressed PCNSL growth <i>in vitro</i> and <i>in vivo</i>. These patient-derived models offer a platform for predicting clinical chemotherapeutics efficacy and provide critical insights into PCNSL pathogenic mechanisms, accelerating therapeutic discovery for this aggressive disease.</p>Significance:<p>A set of clinically relevant CNSL xenografts identifies a hyperactive RelA/p65-hexokinase 2 signaling axis as a driver of progression and potential therapeutic target for treatment and provides a foundational preclinical platform.</p></div>

The Primary Results of R-MTO Regimen (Rituximab, Methotrexate, Thiotepa, and Orelabrutinib) As the First-Line Induction Therapy Followed By Autologous Stem Cell Transplantation in Newly Diagnosed Primary Central Nervous System Lymphoma

Primary central nervous system lymphoma(PCNSL)is a primary brain tumor, which appears commonly and occupies around 4.6% of all primary brain tumors. The standard therapy for this tumor is high-dose methotrexate chemotherapy(HD-MTX)and whole-brain irradiation. No salvage therapies for HD-MTX therapy-refractory or recurrent PCNSLs have been standardized. In our institution, ESHAP therapy(high-dose cytarabine:2,000mg, cisplatin:25mg/m², etoposide:40mg/m², methylprednisolone:500mg)was administered as a secondary chemotherapy, and the efficiency was examined. We administered ESHAP therapy as secondary chemotherapy for patients with refractory/recurrent PCNSL after HD-MTX therapy. Patients with PCNSL who were diagnosed and treated at our institute since 1996 were retrospectively studied. Clinical evaluations were performed based on Karnofsky Performance Status and overall survival, and the effect of ESHAP therapy was evaluated using the Response Assessment in Neuro-Oncology criteria. The number of patients with refractory/recurrent PCNSLs were 18(28-77 years of age, median age of 58.5 years). The response rate(RR)after the first course of salvage ESHAP therapy was 77.8%(14 cases), and complete response(CR)was achieved in 6 cases. The RR after the final course of ESHAP therapy was as high as 61.1%(11 cases), and 4 patients retained CR status. In patients with refractory PCNSL who were treated with HD-MTX, the RR in the final course of salvage ESHAP therapy was as high as 77.8%(7 cases), and 3 patients retained CR status during the periods. The occurrence rate of Grade 3 or higher adverse events, according to the Common Terminology Criteria for Adverse Events version 4.0, was 66.7%(12 cases);all events that were associated with blood and lymphatic system disorders were quickly alleviated, and no fatal adverse events occurred. In this study, we retrospectively examined the efficacy of ESHAP therapy as a secondary chemotherapy for patients with refractory/recurrent PCNSL after receiving HD-MTX therapy. Based on our findings, we suggest that ESHAP therapy should be considered as an encouraging secondary chemotherapy for patients with refractory/recurrent PCNSL.

Phase 1 investigation of lenalidomide/rituximab plus outcomes of lenalidomide maintenance in relapsed CNS lymphoma

Primary CNS lymphoma (PCNSL) has been increasing in incidence among both immunocompetent and immunocompromised patients. Today there is no uniform approach to the treatment of this disease. Whole brain irradiation (WBI) has been standard treatment, resulting in complete remission in the majority of patients, but with most patients relapsing and dying of their disease within 2 years after treatment. The addition of chemotherapy to WBI appears to prolong survival for patients younger than 60 years with median survival reaching a plateau at approximately 40 months. The issue of the best treatment for older patients remains controversial. Prospective studies will be needed, as it is impossible to draw conclusions from the nonrandomized small series published so far. This is because the prognostic variables of age and performance status to date have affected outcome more than therapy. In this review, some of the questions regarding the management of PCNSL are addressed. Since the role of radiotherapy remains unclear, we designed a new randomized multicenter study (G-PCNSL-SG-1 trial) to investigate the optimal timing of WBI after high-dose methotrexate (HD-MTX) chemotherapy.

Improving the Utilization and Tolerability of Thiotepa-Based Autologous Stem Cell Transplantation in Primary CNS Lymphoma

Prognosis Prediction By Two Single Factors Could Predict the Survival of PCNSL Patients Received HD-MTX Therapy without HSCT

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

Autologous Stem Cell Transplantation (ASCT) Improves Survival Outcome in Primary Central Nervous System Lymphoma (PCNSL) in a Minority Rich, Underserved Inner City Population in the Real-World Setting

Primary central nervous system lymphoma (PCNSL) is an aggressive B cell lymphoma that occurs in immunocompetent and immunosuppressed patients. Primary ocular lymphoma represents an important variant of this disease. The outcome for patients with PCNSL is rapidly improving with new treatment strategies. This review focuses on recent advances, investigations, and controversies in the management of these increasingly important malignancies. The incidence of PCNSL is rising in immunocompetent patients over the age of 60 years for unexplained reasons. However, the incidence of AIDS-related PCNSL, which is related to Epstein-Barr virus infections, has fallen with the institution of highly active antiretroviral therapy. During the past decade, standard therapy has evolved from cranial irradiation to high dose methotrexate-based regimens. This shift in therapy has been associated with an increase in the median survival of patients from 1 year to longer than 3 years, and with an equally striking reduction in neurotoxicity if whole brain radiation is avoided. Optimal therapeutic results require careful attention to opportunistic infections, thromboembolic disease, and renal toxicities associated with high dose methotrexate. Overall, PCNSLs are increasing in frequency and the results of therapy for this disease have dramatically improved during the past decade. Many important therapeutic questions remain unanswered. These include the optimal dose, frequency, and duration of methotrexate, as well as the roles of additional systemic chemotherapy drugs, intrathecal therapy, and cranial irradiation. Further progress in this uncommon disease will depend on entering patients into carefully designed multicenter clinical trials to build upon the significant advances that have been made.

Nivolumab in Primary CNS Lymphoma and Primary Testicular Lymphoma with CNS Involvement: Single Center Experience

Multiomic dissection of immune-privileged DLBCL reveals divergent immune subtypes in testicular and primary central nervous system lymphoma

First-Line Treatment and Outcome of Elderly Patients with Primary Central Nervous System Lymphoma (PCNSL) – A Systematic Review and Individual Patient Data Meta-Analysis