Non Invasive Detection of IDH1/2 Mutation in Gliomas

This trial develops a non invasive diagnostic approach of IDH1 mutated gliomas combining mutation detection from free plasmatic DNA, D-2HG dosage in urine samples, and D-2HG detection by Brain Spectro MRI. In group 1 (25 patients), patients with presumed grade II-III gliomas candidate to surgery will undergo spectro MRI, plasma, urine dosages. Results will then be confronted to tumor mutational status and D-2HG. In group 2 (15 patients), patients with known IDH1 mutation will undergo spectro MRI, plasma, urine dosages overtime in order to correlate results with the response to treatment.