[Results of surgical treatment in patients with neurocytomas of the brain].

Central neurocytoma (CN) is a rare brain neoplasm which is characterized by certain clinical, radiological, and morphological characteristics. This tumor was first described in 1982 by J. Hassoun et al. who found neurosecretory granules and microtubules while microscopically studying 2 patients with oligodendrogliomas of lateral ventricles and concluded that these neoplasms were of neuronal origin. Materials and methods. In 1992 to 2004, a total of 84 patients diagnosed as having CN were treated at the Academician N. N. Burdenko Research Institute of Neurosurgery, Russian Academy of Medical Sciences. In most cases, the tumor showed a clinical picture as elevated intracranial pressure that was detected in 80 (more than 90%) cases. In this series, all neurocytomas were located in the ventricles, mainly in the pellucid septal region; tumor infiltration of the lateral ventricular ependyma and medullary substance invasion into the region of the thalamus and corpus callosum. Computed tomographic scans displayed central neurocytomas as space-occupying lesions of mixed (heterogeneous) density, which frequently contained single and multiple petrificates and cysts. TI-weighted magnetic resonance imaging (MRI) indicated that in most cases (n=56, 66%), the intensity of a signal from the tumor was mixed and similar to that of the white matter of the brain. These masses were characterized by the presence of tumor structural cysts that were better visualized on T2-weighted tomograms. The tumor was removed in 83 cases; 2 out of them had previously undergone stereotactic biopsy (STB). STB was performed alone in one case. Transcallous, transcortical-through-premotor-area, combined, and transcallous-transcortical approaches were applied when the neurocytomas were removed. Results. Total removal of a tumor (when its remains were not visualized by postoperative MRI) was achieved in 11 (13%) patients. Its subtotal removal was accomplished in 48 (58%) patients. Partial removal was done in 24 (29%) patients. In the early postoperative period after tumor removal, there was a worse health status along with a transient progression of cerebral and focal symptoms in most patients with CN. The magnitude, pattern, and duration of these changes differed. Conclusion. The long (from several months to several years) history of the disease and young age (14 to 59 years) are typical of patients with CN. The tumors are located intraventricularly, more commonly along the midline, and they have well-defined X-ray signs: these are well-circumscribed tumors of heterogeneous density, which frequently contain single and/or multiple cysts and petrificates; there is a moderate contrast enhancement. The basic way of improving the results of treatment in patients with CN is the latter's early diagnosis and surgery when the tumor is locally advanced within the ventricular system.