Management of supratentorial low-grade gliomas.

Low-grade gliomas are a clinically, radiographically, and pathologically diverse group of central nervous system neoplasms. Treatment decisions are based primarily on histologic tumor type and patient age. Pilocytic astrocytomas tend to occur in younger patients, are circumscribed, and amenable to cure with gross total resection. There is no role for the routine use of postoperative radiotherapy in these patients. In contrast, infiltrative tumors, including ordinary (nonpilocytic) astrocytomas, mixed oligoastrocytomas, and oligodendrogliomas occur in middle-aged patients and are generally not curable, even with gross total resection. Postoperative radiotherapy of these infiltrative tumors appears to improve survival, particularly in adults. Several ongoing clinical trials are addressing two issues: Observation vs radiotherapy and low-dose vs high-dose radiotherapy in patients with ordinary astrocytomas, oligoastrocytomas, and mixed oligoastrocytomas.