Two molecular subtypes of skull base meningiomas with extracranial extension

classification.However, the implementation of such approaches in routine clinical practice remains limited due to their technical complexity and cost constraints.To address this, we sought to classify meningiomas using only data obtained from WES, focusing specifically on somatic mutations and CNAs.Meningiomas were initially classified into three molecular groups [10], and subsequent studies have proposed overlapping classification systems that refine or expand upon this original framework [2,8,12], including approaches that integrated transcriptomic, epigenomic, and genomic data to capture the biological features of meningiomas with greater resolution.In this cohort, tumors were classified into three groups based on driver mutations and CNAs: Group A comprised NF2-wildtype tumors, including those harboring driver mutations such as TRAF7, KLF4, AKT1, SMO, or POLR2A, as well as tumors without detectable driver mutations or high-risk CNAs.Group B included tumors with NF2 mutation/22q loss but lacking high-risk CNAs.Group C consisted of tumors harboring high-risk CNAs, either with known driver mutations or without other known drivers (Fig. 1A).Speficially, 1p loss, 6p/q loss, 10p/q loss, 14q loss, and 18p/q loss were defined as high-risk CNAs in accordance with previous publications [5,8,12].An 80% threshold of chromosomal arm involvement was used to define arm-level events.Tumor location was classified into four categories: (1) anterior