IDH2 and central nervous system cancer: Concerning IDH-mutant gliomas, combinations of amide and amine (but not amide/amine ratio) metrics may be also useful biomarkers for differentiating other glioma subgroups: (i) IDH-mutant_1p/19qret from IDH-mutant_1p/19qcodel and (ii) IDH-mutant_1p/19qret with AB/FS mismatch from IDH-mutant_1p/19qret without AB/FS mismatch.