However, other variables reported to be associated with patient overall survival and routinely measured, like tumor malignancy, O6-methylguanine-DNA methyltransferase (MGMT) promoter methylation status [28,29], isocitrate dehydrogenase 1 (IDH1) mutational status [30], and patient gender and age, were also included when calculating patients’ survival probability with the purpose to significantly improve it. Here, MGMT is linked to neoplasm.