NIMG-38. 2-HYDROXYGLUTARATE MAGNETIC RESONANCE SPECTROSCOPY IN ADULT BRAINSTEM GLIOMA PATIENTS

Abstract INTRODUCTION The onco-metabolite, 2-hydroxyglutarate (2HG), is non-invasive biomarker detected by magnetic resonance spectroscopy (MRS), indicating isocitrate dehydrogenase (IDH) mutant glioma. Especially in patients with brainstem lesions where biopsies are at high risk of causing neurological deficit, 2HG-MRS may be useful. Here, we examined the utility for diagnosing IDH adult diffuse glioma and ability prognosis prediction. METHODS Three tesla -MRS (3T-MRS) was performed on radiographically confirmed tumor. A single-voxel set lesion reference to T2 / FLAIR image, analyzed according 2HG-tailored MRS protocol (Philips, Achieva, PRESS, TE 35 ms). All underwent biopsy using an intraoperative navigation system (Brain LABTM) or stereotactic (Komai’s CT-stereotactic frame) before initial treatment. H3K27M mutation status were immunohistochemistry DNA sequence. We relationship between 2HG values patient survival period. RESULTS Ten (7 male 3 female, median age 33.5) biopsy. Four had 4 (1 R132H, 2 R132S, 1 R132G). Two neither nor mutation. H3-K27 mutations mutually exclusive. tumor located pons mainly. There no significant radiological difference conventional MRI Pearson's chi-square test demonstrated that concentrations > 1.5 mM 100% sensitivity 83.3% specificity (p = 0.0098). overall 130.5 months (n=4) 25 wild-type (n=6), respectively. CONCLUSIONS 3T-MRS able detect noninvasive study helpful diagnosis predicting patient.