Can MGMT promoter methylation status be used as a prognostic and predictive marker for glioblastoma multiforme at the present time?

Excerpt

Several studies have addressed the prognostic and predictive value of the methylation status of the O6-methylguanine-DNA methyltransferase (MGMT) gene in patients with glioblastoma multiforme (GBM). In a translational study analyzing the randomized EORTC-26981-22981/NCIC-CE3 trial by Stupp et al. [9], Hegi and coworkers [4] first demonstrated that the benefit of combined radiotherapy and temozolomide chemotherapy over radiotherapy alone was significant in GBM patients with a methylated MGMT promoter (median survival: 21.7 versus 15.3 months; p < 0.001), but only slight and borderline significant in those with an unmethylated status (median survival: 12.7 versus 11.8 months; p < 0.06). MGMT promoter methylation was found to be an independent prognostic factor for survival (hazard ratio: 0.41; p = 0.001). However, these initial results were partly offset by the results of a five-year analysis published by the same group at a later date [8]. In the latter study, the addition of temozolomide to radiotherapy also had a significant beneficial effect in patients with an unmethylated MGMT promoter (median survival: 12.6 vs. 11.8 months; p = 0.035). …