Brain, Central neurocytoma

Central neurocytoma is an uncommon intraventricular neoplasm with neuronal differentiation, classified as WHO grade II. They generally occur in young adults, most commonly in the lateral or third ventricles. Microscopically, they are characterized by uniform round cells with salt-and-pepper chromatin. They may form neurocytomatous rosettes, composed of large anuclear fibrillary areas, or more rarely Homer Wright rosettes. Immunohistochemistry shows staining for neuronal markers, most reliably synaptophysin, NeuN, class III beta tubulin, and MAP2. However, chromogranin-A and neurofilament are usually negative. GFAP is also usually not expressed. Proliferation index is typically low (