Measurement of Elevated 2-Hydroxyglutaric Acid in Brain Tumors By Difference Editing At 3T In Vivo

Changho Choi¹, Sandeep Ganji¹, Zoltan Kovacs¹, Ralph DeBerardinis¹, Elizabeth Maher¹

Recent mass spectroscopy studies in-vitro and ex-vivo indicated that a fraction of gliomas contain mutations of isocitrate dehydrogenase-1 and -2, causing accumulations of 2-hydroxyglutaric acid (2HG). Here, we present in vivo detection of 2HG in human brain tumors by means of difference editing at 3T. The C2-proton resonance of 2HG at 4.02 ppm was edited using a 20 ms Gaussian radio-frequency (RF) pulse for selective 180a rotation of the its coupling partners at ~1.9 ppm. In vivo measurement was conducted in various tumors. The results indicated that 2HG is elevated to 2 - 8 mM in low-grade gliomas and secondary glioblastomas.