Cortical T2-hyperintense lesions as the initial MRI finding in glioblastoma

Early MRI findings in GBM can include ill-defined T2-hyperinsities throughout grey and white matter, often with enhancement. Outside of animal models and a single prior case series, little has been reported on GBM manifesting within cortex. We report a series of three patients in whom GBM initially presented with early cortical findings, indicating that grey matter lesions can be the first detectable radiographic feature in a subset of patients. New-onset seizures may present with similar cortical ribbon changes, creating a diagnostic challenge as illustrated by two of our reported cases who initially presented with seizures and cortical abnormalities. Our series highlights the imperative for short interval imaging follow-up in such patients and indicates the need to consider suspicious cortical lesions when planning the radiation treatment field.