Spectroscopic MRI-Guided Proton Therapy in Non-Enhancing Pediatric High-Grade Glioma

• Type of Material: Article
• Authors: Vicki Huang, Emory University; Abinand Rejimon, Emory University; Kartik Reddy, Emory University; Alexander G Trivedi, Emory University; Karthik K Ramesh, Emory University; Alexander S Giuffrida, Emory University; Robert Muiruri, Emory University; Hyunsuk Shim, Emory University; Bree Eaton, Emory University
• Language: English
• Date: 2023-04-01
• Publisher: MDPI
• Publication Version: Final Published Version
• Copyright Statement: © 2023 by the authors.
• License: Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International
• Final Published Version (URL): http://dx.doi.org/10.3390/tomography9020051
• Title of Journal or Parent Work: TOMOGRAPHY
• Volume: 9
• Issue: 2
• Start Page: 633
• End Page: 646
• Grant/Funding Information: This work is also supported by pre-doctoral fellowship F31 CA247564 (KKR).; This research was funded by Peach Bowl LegACy (BRE) and NIH U01 CA264039 (HS).
• Keywords: BRAIN; RADIATION-THERAPY; CHILDREN; BRICS; pediatric high-grade glioma; spectroscopic MRI; CLOUD PLATFORM; Radiology, Nuclear Medicine & Medical Imaging; TEMOZOLOMIDE; INTELLIGENCE QUOTIENT; proton therapy; Life Sciences & Biomedicine; Science & Technology; RADIOTHERAPY
• Research Categories: Health Sciences, Radiology; Health Sciences, Medicine and Surgery; Health Sciences, Oncology

Abstract

Radiation therapy (RT) is a critical part of definitive therapy for pediatric high-grade glioma (pHGG). RT is designed to treat residual tumor defined on conventional MRI (cMRI), though pHGG lesions may be ill-characterized on standard imaging. Spectroscopic MRI (sMRI) measures endogenous metabolite concentrations in the brain, and Choline (Cho)/N-acetylaspartate (NAA) ratio is a highly sensitive biomarker for metabolically active tumor. We provide a preliminary report of our study introducing a novel treatment approach of whole brain sMRI-guided proton therapy for pHGG. An observational cohort (c1 = 10 patients) receives standard of care RT; a therapeutic cohort (c2 = 15 patients) receives sMRI-guided proton RT. All patients undergo cMRI and sMRI, a high-resolution 3D whole-brain echo-planar spectroscopic imaging (EPSI) sequence (interpolated resolution of 12 µL) prior to RT and at several follow-up timepoints integrated into diagnostic scans. Treatment volumes are defined by cMRI for c1 and by cMRI and Cho/NAA ≥ 2x for c2. A longitudinal imaging database is used to quantify changes in lesion and metabolite volumes. Four subjects have been enrolled (c1 = 1/c2 = 3) with sMRI imaging follow-up of 4–18 months. Preliminary data suggest sMRI improves identification of pHGG infiltration based on abnormal metabolic activity, and using proton therapy to target sMRI-defined high-risk regions is safe and feasible.