Pediatric brain tumors.

Pediatric brain tumors differ from adult brain tumors in several major ways. First, the types of tumors encountered in children are uncommon in adults, and vice versa. Second, tumors of the posterior fossa comprise a far greater percentage of tumors in children as compared to adults. Third, the value of extensive tumor resection, which is controversial for malignant brain tumors in adults, has been confirmed for a variety of childhood brain tumors. Fourth, chemotherapy has been shown to be effective in improving overall outcome in several childhood brain tumors, but has yet to be demonstrated to have a major benefit for adult tumors. In addition, to avoid the morbidity of irradiation on the developing nervous system, chemotherapy is increasingly used to delay or avoid using radiotherapy in children younger than 3 years of age with high-grade and incompletely resected low-grade tumors. Fifth, the prognosis for histologically similar tumors is often more favorable in children than adults. A review of general principles in the clinical presentation, diagnostic evaluation, and treatment of childhood brain tumors is followed by discussion of surgical management, adjuvant therapy, and outcome of the more common types of tumors.