However, after invasive procedures and genomic data collection, extent of resection [7], [13], [14], [15] and molecular criteria, such as O6-methylguanine-DNA-methyltransferase (MGMT) promoter methylation, isocitrate dehydrogenase 1 (IDH1), or glioma CpG island methylator phenotype (G-CIMP) status are significant prognostic and predictive criteria [7], [16], [17], [18]. The gene discussed is MGMT; the disease is central nervous system cancer.