April 1st 2005While the majority of primary central nervous system (CNS) tumors occur in patients over the age of 45 years, they are also the most prevalent solid neoplasms of childhood. About 16% of patients with brain tumors have a family history of cancer, and evidence points to chromosomal and genetic abnormalities. Magnetic resonance imaging (MRI) is superior to computed tomography (CT) in localizing tumors and in evaluating edema, hydrocephalus, and hemorrhage.