Low-grade central nervous system tumors.
Low-grade tumors of the central nervous system constitute 15 to 35% of primary brain tumors. Although this category of tumors encompasses a number of different well-characterized entities, low-grade tumors constitute every tumor not obviously malignant at initial diagnosis. In this brief review, the authors discuss the pathological classification, diagnostic procedures, treatment, and possible pathogenic mechanisms of these tumors. Emphasis is given in the neuroradiological and pathological features of the several entities.