Meningiomas - transition from traditional histological grading to molecular profiling in WHO CNS5: A Review

Despite being the most common primary intracranial tumor, meningiomas are classified largely based on histological features. The current system of grading has been shown to be unsatisfactory due to its poor reproducibility as well as the considerable variability within grades. With the increasing availability of genomic and epigenomic profiling, several markers have been suggested to correlate with the location, histological subtype, and clinical behavior of meningiomas. These developments have enabled the development of targeted therapy, as well as individualized use of currently available adjuvant methods. These include copy number alterations (CNAs), specific genetic abnormalities (germline and sporadic), and genome-wide methylation profiles. In this review, we recapitulate the changes in the classification of meningiomas thus far, discuss the various histological subtypes recognized, and present the available literature on the genetic and epigenetic profiles of meningiomas. The recognition and further study of these markers have the potential to usher in an era of personalized therapy in the management of meningiomas, vastly improving outcomes as has been observed in the case of several other tumors.