Exploratory Study of Effects of Radiation Therapy in Pediatric Patients With Central Nervous System Tumors

Background: This exploratory study will be performed in pediatric patients with CNS tumors who are undergoing radiation therapy to investigate pathophysiologic effects of radiation on the CNS. The study includes the analysis of blood, urine, and CSF (if available) to measure biological markers involved with angiogenesis, blood: brain barrier integrity, and neurotoxicity. It also entails comprehensive MR imaging techniques and neuropsychological testing in an effort to correlate changes with biomarker measurements. Objectives: 1. To detect changes in angiogenesis related to radiation of the CNS by: * Measurement of VEGF, bFGF, thrombospondin, TNF-alpha, IL-12, IL-8, and MMP in blood and urine specimens. * MR perfusion and DEMRI. 2. To describe changes in blood:brain barrier permeability associated with radiation of the CNS. 3. To characterize neurotoxicity by: * Measuring biomarkers associated with neurotoxicity * Documenting changes in neurobehavioral functioning through longitudinal comprehensive assessments * Describing changes in quality of life (QOL) * Assessing changes in memory * Defining changes in ophthalmologic studies associated with radiation. * Detecting changes in audiometry associated with radiation. Eligibility Criteria: * Patients must have a primary CNS tumor for which radiation therapy is recommended. * Patients must be less than or equal to 21 years of age. * Prior/Concurrent: Patients will be eligible if they have not received prior radiation. Patients who have undergone surgery or received chemotherapy are eligible. * Performance Status: Patients will be eligible regardless of performance score. Design: This minimally invasive study is designed to explore various biologic effects of radiation on the pediatric CNS in an attempt to 1) obtain information on the pathophysiology of radiation-induced damage, 2) explore the association of neuropsychological deficits with biologic markers and neuroimaging abnormalities, 3) document changes in neurobehavioral functioning through longitudinal comprehensive neuropsychological assessments with comparison of various radiation therapy techniques, 4) describe changes in quality of life in pediatric patients who have received radiation therapy, and 5) attempt to identify children at increased risk of radiation-induced neurotoxicity.