PIK3CA and meningioma: Some key molecular alterations that could impact clinical management of patients with meningioma are [63] copy number alterations (CNAs), which determine alterations to the relations between oncogene and tumor suppressor activity, including: loss of chromosomes 22q, 1p, 14q, and 18q; mutations of genes NF2, TERTp, AKT1, PIK3CA, SMO, SUFU, TRAF7, KLF4, SMARCE1, BRCA1-associated protein 1 (BAP 1), Duchenne muscular dystrophy gene (DMD), PBRM1, POLR2A, and CDKN2A/B; homozygous deletions; epigenomic alterations; H3K27me3 alterations; TIMP3 methylation; and TP73 promoter (TP73p) methylation.