IDH1 and glioblastoma: Moreover, although PMT was initially described as a “frequent” event and post-therapeutic characteristic of GBM [114, 166], a longitudinal transcriptome analysis performed by Wang et al. showed that 55% of tumors from IDH-wildtype GBM patients retained their original transcriptional subtype at recurrence and also that the frequency of PMT was not significantly higher than that of other subtype transitions [161].