The 2016 revised fourth edition of the World Health Organization (WHO) classification of central nervous system (CNS) tumors incorporated molecular features with histologic grading, revolutionizing ...how oncologists conceptualize primary brain and spinal cord tumors as well as providing new insights into their management and prognosis. The 2021 revised fifth edition of the WHO classification further integrates molecular alterations for CNS tumor categorization, updating current understanding of the pathophysiology of many of these disease entities. Here, the authors review changes in the new classification for the most common primary adult tumors—gliomas (including astrocytomas, oligodendrogliomas, and ependymomas) and meningiomas—highlighting the key genomic alterations for each group classification to help clinicians interpret them as they consider therapeutic options—including clinical trials and targeted therapies—and discuss the prognosis of these tumors with their patients. The revised, updated 2021 WHO classification also further integrates molecular alterations in the classification of pediatric CNS tumors, but those are not covered in the current review.
The 2021 World Health Organization classification of tumors of the central nervous system increasingly relies on molecular alterations for central nervous system tumor categorization. The new classification will help improve diagnosis, prognosis, and treatment selection (including enrollment into relevant clinical trials) for patients with brain tumors.
Primary central nervous system lymphoma is a rare subtype of non‐Hodgkin lymphoma that is confined to the brain, leptomeninges, or the eye and is associated with a relatively poor prognosis compared ...to other extranodal diffuse large B‐cell lymphomas. However, methotrexate‐based induction chemotherapy followed by consolidative chemotherapy or high‐dose therapy and autologous stem cell transplantation is associated with improved survival and reduced neurotoxicity. Aberrant activation of B‐cell receptor signaling and activation of nuclear factor kappa beta is a frequent genetic alteration and offers opportunities for targeted therapies in this lymphoma subtype.
Anti-angiogenic therapy has become an important component in the treatment of many solid tumors given the importance of adequate blood supply for tumor growth and metastasis. Despite promising ...preclinical data and early clinical trials, anti-angiogenic agents have failed to show a survival benefit in randomized controlled trials of patients with glioblastoma. In particular, agents targeting vascular endothelial growth factor (VEGF) appear to prolong progression free survival, possibly improve quality of life, and decrease steroid usage, yet the trials to date have demonstrated no extension of overall survival. In order to improve duration of response and convey a survival benefit, additional research is still needed to explore alternative pro-angiogenic pathways, mechanisms of resistance, combination strategies, and biomarkers to predict therapeutic response.
Low‐Grade Gliomas Forst, Deborah A.; Nahed, Brian V.; Loeffler, Jay S. ...
The oncologist (Dayton, Ohio),
April 2014, Volume:
19, Issue:
4
Journal Article
Peer reviewed
Open access
Low‐grade gliomas (LGGs) are a diverse group of primary brain tumors that often arise in young, otherwise healthy patients and generally have an indolent course with longer‐term survival in ...comparison with high‐grade gliomas. Treatment options include observation, surgery, radiation, chemotherapy, or a combined approach, and management is individualized based on tumor location, histology, molecular profile, and patient characteristics. Moreover, in this type of brain tumor with a relatively good prognosis and prolonged survival, the potential benefits of treatment must be carefully weighed against potential treatment‐related risks.
We review in this article current management strategies for LGG, including surgery, radiotherapy, and chemotherapy. In addition, the importance of profiling the genetic and molecular properties of LGGs in the development of targeted anticancer therapies is also reviewed. Finally, given the prevalence of these tumors in otherwise healthy young patients, the impact of treatment on neurocognitive function and quality of life is also evaluated.
This article reviews current management strategies for low‐grade gliomas (LGG), including surgery, radiotherapy, and chemotherapy. In addition, the importance of profiling the genetic and molecular properties of LGGs in the development of targeted anticancer therapies is also reviewed. Finally, given the prevalence of these tumors in otherwise healthy young patients, the impact of treatment on neurocognitive function and quality of life is also evaluated.
Pleomorphic xanthoastrocytoma (PXA) is low-grade glial neoplasm principally affecting children and young adults. Approximately 40% of PXA are reported to recur within 10 years of primary resection. ...Upon recurrence, patients receive radiation therapy and conventional chemotherapeutics designed for high-grade gliomas. Genetic changes that can be targeted by selective therapeutics have not been extensively evaluated in PXA and ancillary diagnostic tests to help discriminate PXA from other pleomorphic and often more aggressive astrocytic malignancies are limited. In this study, we apply the SNaPshot multiplexed targeted sequencing platform in the analysis of brain tumors to interrogate 60 genetic loci that are frequently mutated in 15 cancer genes. In our analysis we detect BRAF V600E mutations in 12 of 20 (60%) WHO grade II PXA, in 1 of 6 (17%) PXA with anaplasia and in 1 glioblastoma arising in a PXA. Phospho-ERK was detected in all tumors independent of the BRAF mutation status. BRAF duplication was not detected in any of the PXA cases. BRAF V600E mutations were identified in only 2 of 71 (2.8%) glioblastoma (GBM) analyzed, including 1 of 9 (11.1%) giant cell GBM (gcGBM). The finding that BRAF V600E mutations are common in the majority of PXA has important therapeutic implications and may help in differentiating less aggressive PXAs from lethal gcGBMs and GBMs.
Abstract
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.
We review the preclinical and clinical experience with first and subsequent generation Bruton's tyrosine kinase inhibitors in B-cell lymphoproliferative diseases, highlighting the rationale for their ...clinical use in primary central nervous system diffuse large B-cell lymphoma (PCNSL).
Growing knowledge on the molecular and genetic profile of PCNSL has provided the basis for new drug development targeting aberrantly activated oncogenic signal transduction pathways. PCNSL exhibits frequent genetic alterations of components of the B-cell and Toll-like receptor signalling pathways. On the basis of these discoveries and the limited efficacy obtained with chemotherapy in refractory and relapsed PCNSL, activity of new targeted agents, such as Bruton's tyrosine kinase inhibitors, has been explored with promising results.
Innovative therapeutic strategies, applied in first line, have contributed to improved outcomes in patients with PCNSL, making this disease potentially curable in young and fit patients. However, response to induction therapies remains suboptimal and the best consolidative therapy has yet to be defined. In this regard, given the activity of Bruton's tyrosine kinase inhibitors in the refractory and relapsed PCNSL setting, these agents are currently being explored as part of combination regimens for induction therapy of newly diagnosed PCNSL.
Abstract
Novel insights into the pathophysiology of primary central nervous system lymphoma (PCNSL) have identified the B-cell receptor and Toll-like receptor pathway as well as immune evasion and ...suppressed tumor immune microenvironment as a key mechanism in the pathogenesis of PCNSL. Small molecules and novel agents targeting these aberrant pathways have been introduced into clinical trials targeting the recurrent or refractory PCNSL patient population. Agents like the Bruton tyrosine kinase (BTK) inhibitor ibrutinib or immunomodulatory drugs (IMiDs) like pomalidomide and lenalidomide have shown promising high response rates in the salvage setting. Here, we give an overview about the recent, exciting developments in PCNSL and summarize the results of clinical trials using novel agents in the recurrent and refractory salvage setting, which include immune checkpoint inhibitors, IMiDs, as well as BTK, phosphatidylinositol-3 kinase, and mammalian target of rapamycin inhibitors.
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