Article

Primary brain tumors comprise a large group of malignant and non-malignant tumors
including heterogeneous entities with various biological and clinical behaviors.
Up till recently, diagnosis of brain cancers, that drives treatment
decision-making, was based on integration of clinical, radiological and
pathological features of patients and tumors. Over the last years, practical
neuro-oncology has entered an era of molecular-based personalized medicine.
Indeed, molecular features of tumors provide critical information to physicians
for daily clinical management of patients and for design of relevant clinical
research. Sporadic gliomas or glial tumors are the most common primary brain
tumors in adults. Recently, their medical management has been revolutionized by
molecular data. Indeed, optimal therapeutic management of grade III glioma
patients now requires assessment of chromosome arms 1p/19q copy number and IDH
mutational statuses as predictive and prognostic biomarkers. Indeed, two large
phase III clinical trials have demonstrated that early chemotherapy plus
radiotherapy, versus radiotherapy alone, doubles median overall survival of
patients suffering from 1p/19q co-deleted and/or IDH mutated anaplastic
oligodendroglial tumor. Interestingly, both biomarkers have been identified in a
large proportion of WHO grade II gliomas. Their clinical value, in this
population, is under investigation through multiple phase III clinical trials. In
sporadic WHO grade I gliomas, and specifically in pilocytic astrocytomas, MAPK
signaling pathway activation is a frequent event, mainly due to genetic
alterations involving BRAF gene. This characteristic opens new therapeutic
perspectives using MAPK signaling pathway inhibitors. Finally, in the most
aggressive gliomas, WHO grade IV gliomas, two critical biomarkers have been
identified: (i) MGMT promoter methylation associated with longer survival and
better response to chemotherapy and (ii) IDH mutations predicting better
prognosis. Although, further studies are needed, MGMT promoter methylation will
undoubtedly be transferred soon to clinical practice. Molecular characteristics
are beginning to be valuable and indispensable in neuro-oncology for better
management of brain tumors patients. The near future will be marked by
identification of novel molecular biomarkers and their validation for clinical
practice.
CI - Copyright (c) 2015 Elsevier Masson SAS. All rights reserved.

Langue : ANGLAIS