MRI and Blood Biomarkers for the Prediction of Neurocognitive Decline Following Brain Radiation

PRIMARY OBJECTIVE: I. To describe changes of image features on conventional T1- and T2- weighted imaging, and quantitative changes on multiparametric MRI including apparent diffusion coefficient (ADC), fractional anisotropy (FA), relative cerebral blood volume (rCBV), fractional volume of the extravascular, extracellular space (ve) and Ktrans (transfer constant that characterizes the diffusive transport of low-molecular weight gadolinium across the capillary endothelium) associated with neurocognitive changes following radiation. SECONDARY OBJECTIVES: I. To identify biofluid biomarkers at baseline and dynamics of biomarkers after radiation exposure that are associated with neurocognitive changes. II. To model a composite early biomarker (baseline or within 3 weeks of the start of radiotherapy) that incorporates the most promising imaging and biofluid biomarkers to predict for later neurocognitive decline. III. To evaluate the relationship between the delivered radiation dosimetry to brain subregions and patterns of neurocognitive decline in order to inform potential subregions of focus for future pre-clinical and clinical investigation. IV. To evaluate the relationship between quantitative changes on multiparametric MRI including apparent diffusion coefficient (ADC), fractional anisotropy (FA), relative cerebral blood volume (rCBV), fractional volume of the extravascular, extracellular space (ve) and Ktrans (transfer constant that characterizes the diffusive transport of low-molecular weight gadolinium across the capillary endothelium) with radiation dosimetry. EXPLORATORY OBJECTIVE: I. To explore changes on advanced MR measurements of structural connectomics, functional connectomics, working memory network, cerebrovascular reactivity (CVR), cerebral blood flow (CBF) and brain metabolism associated with neurocognitive changes following radiation. OUTLINE: Patients undergo multiparametric MRI with contrast at baseline, 3 weeks during radiotherapy, and at 1, 3, 6, 12, and 24 months post-radiotherapy. Patients undergo multiparametric MRI without contrast at 1, 2, 4, 5, and 6 weeks during radiotherapy. Patients may undergo functional MRI at baseline and 6 months post-radiotherapy. Patients also complete questionnaires and undergo collection of blood samples at baseline, weekly through week 6 during radiotherapy, and at 1, 3, 6, 12, and 24 months post radiotherapy.