Neuroimaging of Peptide Based Vaccine Therapy in Pediatric Brain Tumors: Initial Experience

Abstract

The potential benefits of peptide-based immunotherapy for pediatric brain tumors is currently under investigation with pilot studies at our institution. We have noted the presence of treatment-related heterogeneity, which has resulted in radiographic challenges including that of pseudoprogression. Conventional MRI has limitations in the assessment of these different forms of treatment-related heterogeneity, particularly in regards to distinguishing true tumor progression from efficacious treatment responses. Our initial results suggest that advanced neuroimaging techniques, including diffusion MR, perfusion MR and MR spectroscopy may add value in the assessment of treatment-related heterogeneity. Our initial observations suggests that recent delineation of specific response criteria for immunotherapy of adult brain tumors (iRANO) is likely to be relevant to the pediatric population and further validation in multi-center pediatric brain tumor peptide-based vaccine studies are warranted.