D-2-hydroxyglutarate (D-2-HG) is a well-established oncometabolite of isocitrate dehydrogenase (IDH) mutant gliomas. While prior studies have demonstrated that D-2-HG is elevated in the cerebrospinal fluid (CSF) of patients with IDH-mutant gliomas1,2, no study has determined if CSF D-2-HG can provide a plausible method to evaluate therapeutic response. We are obtaining CSF samples from consenting patients during their disease course via intra-operative collection and Ommaya reservoirs. D-2-HG and D/L-2-HG consistently decreased following tumor resection and throughout chemoradiation in patients monitored longitudinally. Our early experience with this strategy demonstrates the potential for intracranial CSF D-2-HG as a monitoring biomarker for IDH-mutant gliomas.

The authors have declared no competing interest.

This study was funded by: National Institutes of Health NINDS R61 NS122096 to TCB, TJK, JEP, PAD, SHK, AEW; National Institute of Health T32GM065841 to CRC.

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Yes

The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

The Mayo Clinic Institutional Review Board at Rochester, MN approved this study.

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All data produced in the present study are available upon request to the author.