BIOM-14. INCREASED RATIO OF GLUTAMATE TO TOTAL CREATINE IN GLIOBLASTOMA PATIENTS WITH THE POST-OPERATIVE EPILEPSY

Abstract

Abstract Epilepsy in glioblastoma patients significantly reduces their quality of life; however, little is known about the association between predicting epilepsy and metabolites in tumors. In this study, we used 3.0-T magnetic resonance imaging (MRI) and 1H-magnetic resonance spectroscopy (MRS) to quantify metabolite concentrations in patients with varying epilepsy histories. MRS data were quantified with linear combination model (LC-Model) software. From January 2013 to April 2020, fifty-one patients with primary glioblastoma underwent pretreatment 3.0-T MRI/1H-MRS scanning. Twenty-one patients (41%) suffered from epilepsy during the postoperative course, although forty-seven patients (97%) took anti-epileptic drug after surgery. MRS data were compared between groups with and without the post-operative epilepsy. The higher ratios of glutamate (Glu) and glutamate + glutamine (Glx) to total creatine (tCr) in the tumor were significantly associated with epilepsy history (Glu/tCr P < 0.001, Glx/tCr P = 0.004, respectively). The receiver operating characteristic curve analysis showed that a Glu/tCr value of 1.81 was 70% sensitive and 90% specific for the prediction of epilepsy during the postoperative course (area under curve: 0.82). These results suggest that the Glu/tCr ratio in tumors can be a predictive maker for early detection of epileptic seizures after surgery in glioblastoma patients.