Central neurocytoma--case report.

The authors present a case of central neurocytoma in a 34-year-old female who had experienced intermittent headaches over a 10-year period. On computed tomographic (CT) scans and magnetic resonance images, the tumor appeared as a large, calcified mass occupying both lateral ventricles. A right parieto-occipital craniotomy was performed and the tumor was totally removed. While the light microscopic findings suggested a diagnosis of oligodendroglioma, electron microscopic examination demonstrated clear vesicles, microtubules, and synaptic structures within the abundant cytoplasmic processes of the tumor cells. Immunohistochemical examination showed the tumor cells to be strongly positive for neuron-specific enolase, sparsely positive for S-100 protein, and negative for glial fibrillary acidic protein. The final histological diagnosis was central neurocytoma. The postoperative course was uneventful and no further treatment was administered. She has no neurological deficits and CT has shown no evidence of recurrence during the 2 years since her surgery. Central neurocytoma is a rare tumor arising in the lateral ventricle, and the diagnosis is mainly based on electron microscopic findings. Since central neurocytoma appears to have a good prognosis following total removal alone, it is very important to distinguish between this and other ventricular tumors.