DSC-MRI Fractional Tumor Burden (FTB) Maps: An Early Predictor of Response to Tumor Treating Fields in Glioblastoma

Motivation: Tumor treating fields (TTFields) is a novel treatment modality for patients with newly diagnosed and recurrent glioblastoma (GBM). How to best monitor response to TTFields remains unclear with conventional MRI shown to be unreliable. Goal(s): Fractional tumor burden (FTB) maps, derived from DSC-MRI perfusion imaging, were evaluated for this purpose. Approach: Conventional and perfusion MRI data were collected before and up to 6 months after TTField treatment. Changes in conventional and FTB metrics were evaluated for their ability to predict outcomes. Results: Change in FTB at 1-2 months post treatment initiation provide an early indicator of response to TTFields. Impact: Use of perfusion-derived fractional tumor burden (FTB), as an early indicator of response to Tumor Treating Fields, overcomes current limitations with conventional MRI that should substantially alter how these patients are managed.