Treatment of central neurocytomas.

Central neurocytomas are uncommon tumors of the CNS, representing approximately 0.1-0.5% of all primary CNS tumors. Patients most often present with symptoms of increased intracranial pressure (headache, nausea/vomiting, diplopia) due to obstructive hydrocephalus. Rarely, central neurocytomas may present with a hemorrhage. Central neurocytomas are intraventricular tumors with a predilection for arising in either the lateral or third ventricles. CT or MR cranial imaging demonstrates a circumscribed mass in the ventricles, frequent calcification and moderate contrast enhancement. Surgery provides definitive treatment, as little evidence exists as to response of these tumors to either radiotherapy or chemotherapy. Histopathology reveals a homogenous neoplastic cell population with neuronal differentiation, frequent calcification, occasional perivascular pseudorosettes and infrequent mitoses. Uncommonly, anaplastic variants of central neurocytomas (malignant central neurocytomas) are encountered and are distinguished by frequent mitoses, necrosis and endothelial cell proliferation. Following complete resection, central neurocytomas have a favorable prognosis usually obviating the need for either radiotherapy or chemotherapy.