Even though the majority of studies have shown MGMT IHC does not correlate with patient survival [24], [29], [30], [34], Capper et al. showed that if the test is done before radiation and chemotherapy, if evaluation is done with special attention to the infiltration zone of diffuse astrocytomas, and if glioma grade is taken into account for cutoff values, then an IHC result of greater than 15% positively stained nuclei can indeed predict survival in GBM patients [21]. This evidence concerns the gene MGMT and central nervous system cancer.