Central neurocytoma. A clinico-pathologic study of five cases.

Five cases of central neurocytomas are described. The tumors occurred in relatively young patients (range 14 to 43 years; mean age, 27) with no predilection for sex. All the lesions were located in the anterior portion of the lateral ventricles or in the third ventricle, involving the septum pellicidum or the fornix. Histologically, they were composed of uniform cells with round nuclei and clear cytoplasm resembling oligodendrogliomas or, to a lesser extent, ependymomas. In 4 tumors, protein cell nuclear antigen immunostaining showed a low cell proliferation rate. All cases were positive for neuron-specific enolase. Four of the 5 cases were strongly immunoreactive for synaptophysin. The immunohistochemical data were consistent with neuronal differentiation. Resection was subtotal in 4 cases and total in one. Postoperative radiotherapy was given in only one case. The follow-up revealed a good prognosis: 4 patients were alive and had a long survival (from 2 to 8 years). Only one patient died after 14 months for causes unrelated to the neoplasm. The authors emphasize the importance of immunohistochemistry to recognize this benign intraventricular tumor.