Meningiomas are the most common primary tumors of the central nervous system in adults. Most of the cases are characterized by an indolent behavior, but aggressive cases necessitating repeated surgery and oncological therapy mean a huge clinical burden.

Clinical characteristics and classical histopathological grading scheme (grade 1-3) provide important prognostic information, but are apparently insufficient in a significant subset of meningioma cases. However, following the significant research efforts of recent years, a much more precise, integrated diagnostics emerges. These novel risk-stratification methods are summarized here.

Besides the review of the recent literature, advances of meningioma classification are highlighted through the experiences of our institution, represented by data from a grade 3 meningioma cohort and some selected cases.

Regarding low-grade meningiomas, identification of unexpectedly aggressive cases as well as correct classification of tumors being borderline between low and intermediate risk mean the largest challenge. According to recent data, genomic methylation profile analysis and copy number variation (CNV) patterns seem to be an effective tool in these cases. A scoring system integrating the WHO grade, methylation family and CNV profile with robust prognostic power was recently proposed to address this issue. Prognostic markers in grade 3 meningiomas were also intensively studied in recent years. Our anaplastic meningioma cohort clearly reproduced previously reported value of classical clinico-pathological parameters, such as extent of resection, de novo or progressed type and mitotic activity. Besides defining grade 3 meningiomas irrespectively of the morphology, mutations of the promoter region of TERT gene (pTERT) and homozygous deletion of the CDKN2A/B locus indicate poor prognosis in this subgroup as well. Loss of expression of the lysine-27-trimethylated form of histone H3 (H3 K27me3) also predicts aggressive behavior in meningiomas of all grades, but is the most frequent in grade 3 cases.

In summary, extensive research on the meningioma field resulted in significant progress towards an accurate classification integrating histological and molecular data and providing clinically meaningful prognostic information.