Relaxation-compensated CEST imaging of the APT can predict response to radiotherapy and progression-free survival in patients with glioma at 3T

Motivation: There is a scarcity of studies comparing the clinical value of asymmetry- and different Lorentzian-fit-based CEST contrasts of the amide proton transfer (APT) and semi-solid magnetization transfer (ssMT) in patients with glioma. Goal(s): To assess and compare the potential of asymmetry-based (APTwasym) and Lorentzian-fit-based CEST imaging with (MTRRexAPT and MTRRexMT) and without (MTconst) relaxation compensation for the prediction of therapy response and survival in patients with glioma. Approach: 78 study participants prospectively underwent CEST MRI at baseline before radiotherapy. Results: Imaging of the MTRRexAPT and MTRRexMT predicted response to radiotherapy, whilst the MTRRexAPT was also associated with progression-free survival. Impact: Here we demonstrate for the first time that Lorentzian-fit-based CEST imaging of the APT and ssMT with relaxation compensation can predict therapy response and progression-free survival of patients with glioma at baseline before radiotherapy, at 3T.