Factors associated with poor overall survival by univariate analysis were: Poor performance status (p < 0.001), higher age (p < 0.001), corticosteroid use (p < 0.001), un-methylated MGMT (p < 0.001), multifocal disease (p < 0.001), biopsy compared to resection (p < 0.001), extent of resection defined by post-operative MRI (p = 0.001) and by the surgeon (p < 0.001), and secondary glioblastoma (p = 0.004). This evidence concerns the gene MGMT and glioblastoma.