Latest Findings on Meningioma:WHO grades 1/2/3

Abstract

While most meningiomas are histologically benign tumors, higher grade meningiomas classified as WHO grades 2 and 3 are not always amenable to the standard treatment. To accurately assess the biological characteristics and prognosis of the tumor, the WHO classification of meningiomas has been continuously revised based on the latest findings. This article describes the recent modifications of the WHO classification of meningiomas. In the 2021 WHO classification, molecular diagnosis was considered more important and it was integrated into the classification as a stand-alone criterion of some subtypes. As for treatment, surgical resection is the mainstay treatment for meningiomas of all WHO grades while the importance of radiation therapy should be emphasized, especially for skull base meningiomas, to balance the surgical risk and for functional preservation. Among the new surgical techniques, endoscopic resection of midline skull base meningiomas has been established over the last decades. In addition, several notable new insights to control high-grade meningiomas based on prospective observational studies are introduced in this article.