Relaxation-compensated amide proton transfer (APT) MRI is a predictor of survival and progression in high-grade glioma patients

Zielsetzung:

The purpose of this study was to investigate the predictability of patient overall survival (OS) and progression-free survival (PFS) in newly-diagnosed high grade glioma (HGG) patients using relaxation-compensated chemical exchange saturation transfer (CEST) MRI at 7 Tesla (7T).

Material und Methoden:

Twenty-six patients with newly-diagnosed high-grade glioma (WHO grade III-IV) were included in this prospective IRB-approved study. CEST MRI was performed on a 7T whole-body scanner. Predictability of patient OS and PFS were assessed employing relaxation-compensated CEST MRI by means of amide proton transfer (APT), nuclear Overhauser effect (NOE), and downfield NOE-suppressed APT (dns-APT) imaging. Furthermore, OS and PFS predictability were assessed for clinical parameters (age, treatment, and O6-methylguanine-DNA methyltransferase (MGMT) promotor methylation status) and diffusion-weighted imaging (apparent diffusion coefficient). OS and PFS analyses were performed according to the Kaplan-Meier method with two-sided log-rank statistics.

Ergebnisse:

Relaxation-compensated APT imaging was a significant predictor for patient OS (p = 0.009) and PFS (p = 0.012). Median OS/PFS of patients with low tumor signal intensities = 4.23% (signal median) was 411/293 days compared to 292/112 days for patients with increased APT values. Strongest association with PFS was found for the dns-APT metric (p = 0.009). Among the tested clinical parameters, patient age (older/younger 57 years = median, p = 0.005) and treatment (debulking surgery vs. no surgery, p = 0.018) were significant for OS.

Schlussfolgerungen:

APT CEST MRI serves as a predictor of overall survival and progression-free survival in newly-diagnosed, previously untreated glioma patients and may therefore help to customize glioma patient treatment and response monitoring in the future.