Common gene mutations associated with GBM include, epidermal growth factor receptor (EGFR)[6], IDH1[7], PDGFRA[8-10], HDM2[11-13], PIK3CA[14,15], TERT[16], PIK3R1[10,15], PTEN[17,18], TP53[19], CDKN2A[20,21], NF1[22], ATRX[23,24], and RB[25]. The gene discussed is PIK3CA; the disease is glioblastoma.