TMET-04. DETECTING DYNAMIC PYRUVATE TUMOR METABOLISM IN PATIENTS WITH GLIOMA USING HYPERPOLARIZED CARBON-13 METABOLIC IMAGING

Abstract INTRODUCTION Hyperpolarized carbon-13 (HP-13C) MR enables rapid dynamic imaging of metabolic pathways in the human brain using non-toxic, non-radioactive metabolites as tracers. This study presents our unique experience on benefit [1-13C]pyruvate and [2-13C]pyruvate for evaluating patients with glioma. METHODS 132 scans (71 an integrated 13C /1H coil) including steady-state 1H-MRSI (~10 min) HP-13C (60 sec) following injection HP (N=125) or (N=7) were acquired from 46 glioma (18F/28M; 15 IDH-mutant, 27 IDH-wildtype, 4 IDH-status-unknown). Maps temporally-summed 13C-metabolite signals, ratios, kinetic rate constants calculated contrast-enhancing, nonenhancing, normal-appearing-white-matter (NAWM) regions compared to metrics. RESULTS The only adverse event, a single patient, was burning sensation after that resolved saline flush. mean time-to-injection probes 58.6±14.0 sec. Signal-to-noise ratios [1-13C]lactate [13C]bicarbonate within NAWM data 53±39 13±6, respectively. SD/mean repeated injections (N=3) lactate/pyruvate pyruvate-to-lactate conversion rates 3.8±3.1% 6.5±3.1% NAWM, Patients progressive GBM had significantly higher lower bicarbonate/lactate (p< 0.05) contrast- non-enhancing lesions NAWM. Significantly elevated reduced 0.01) found contrast-enhancing nonenhancing regions, whereas choline/NAA 1H-lactate levels similar. showed glutamate/pyruvate pyruvate-to-glutamate T2 contralateral normal-appearing IDH-mutant gliomas, consistent known reprogramming. CONCLUSION demonstrates potential MRI glioma, which provides spatially distinct contrast imaging. Ongoing studies will further characterize metabolism specific subtypes provide biomarkers responses treatment.