Developing sodium MRI for longitudinal assessment of chemotherapy of glioma in a rat model of cancer
Abstract
Glioblastoma (GBM) is an aggressive cancer which presents significant challenges for disease management and treatment. Tissue sodium concentration (TSC) is a sensitive indicator of disease and changes in TSC can be used as a potential biomarker for treatment response. A longitudinal orthotopic C6 GBM model was used to study changes in TSC due to cancer. Animals were imaged with contrast enhanced T1-weighted, T2-weighted and sodium MRI and were either un-treated or received temozolomide (TMZ) treatment. Accurate assessment of TSC was possible for tumour volumes greater than 150mm3 using 3mm isotropic imaging voxels. TSC increased with tumour growth for all animals. However, there were no differences in TSC changes between treated and non-treated animals. Ultimately TSC at endpoint was lower for treated animals, however this difference was not significant. This study demonstrates the feasibility of preclinical sodium MRI at 3T and highlights future potential challenges to overcome for this modality.