In addition, although the majority of investigations have shown that CDKN2A deletions are more frequently identified in HGG when compared to LGG, suggesting a role for CDKN2A pathway in malignant progression [41,42], no significant association was observed between the presence of CDKN2A losses and WHO grading groups (p = 0.1901) in our study, suggesting that this is an early event in initiation and progression of gliomas. This evidence concerns the gene CDKN2A and central nervous system cancer.