These include classic histopathological features corresponding to at least one meningioma subtype, suggestive histopathological features combined with biallelic inactivation of NF2 or other classic drivers of conventional meningioma (TRAF7, AKT1, KLF4, SMO, PIK3CA), clear cell meningioma (SMARCE1) or rhabdoid meningioma (BAP1). This evidence concerns the gene AKT1 and meningioma.