IDH2 and central nervous system cancer: Although immunohistochemical (IHC) and molecular pathological analysis of surgically obtained tumor tissue is still the gold standard for the diagnosis of an IDH mutated glioma [11,12], in vivo diagnosis of IDH mutant glioma patients has been demonstrated by utilizing proton magnetic resonance spectroscopy (1H MRS) to detect 2-HG [13,14,15,16].