The three-tiered grading system of meningiomas (CNS WHO grade) is mainly based on histopathological features [3]; however, CDKN2A/B homozygous deletion and TERT promoter (pTERT) mutation have been recently added as diagnostic criteria for CNS WHO grade 3 meningiomas because of their negative prognostic significance [2]. This evidence concerns the gene CDKN2A and meningioma.