IDH2 and diffuse astrocytoma: In this aspect, our data is fully comparable to other extensive studies where the frequency of IDH R132H mutant forms of GBM, currently diffuse astrocytoma, WHO CNS grade 4, varies by about 10%, with other forms of mutation in IDH1 as well as mutations in IDH2 have been shown to be rare entries, rather than a statistically significant form of mutation [6].