Molecular-Structural MRI Mismatch for Preoperative Risk Stratification of Pediatric Neuroblastoma.

Purpose To establish molecular-structural mismatch indexes and explore their potential for the preoperative risk stratification of individuals with pediatric neuroblastoma. Materials and Methods In this prospective study, 102 pediatric individuals with suspected neuroblastoma were initially enrolled and underwent structural MRI and amide proton transfer (APT) MRI from April 2019 to November 2023. A four-pool Lorentzian fitting model was employed to minimize motion artifacts and extract the APT signal from confounding factors, generating APT maps and APT-weighted (APTw) images. Novel molecular-structural mismatch images were then synthesized using APT maps, APTw images, and conventional structural MRI. The mean tumor region of interest values on APT, APTw, and mismatch images were compared across risk groups using Wilcoxon rank sum tests; receiver operating characteristic analysis was used to assess the performance of these values in risk stratification, and the DeLong test was used to evaluate differences in the area under the curve (AUC). Results The final analysis included 71 participants (mean ± SD age at examination, 45.8 months ± 31.6; 52 male individuals), comprising 42 participants at high risk and 29 at non-high risk. The mean tumor region of interest values on APT, APTw, and mismatch images were greater in those at high risk than those not at high risk (