Sudden Unexpected Death from Extraventricular Neurocytoma. A Case Report and Review of the Literature

Central neurocytomas (CNs) are benign tumors which usually arise from the lateral ventricles [1,2]. Extra ventricular neurocytomas (EVNs) refer to tumors with similar or identical biological and histopathological characteristics to CNs, but which arise from extra ventricular parenchymal tissue [2]. EVNs may occur at any age, but are usually seen in the third decade of life without sex preference [3]. Presenting symptoms obviously vary depending on the location of the tumor [4]. Histo pathologically, EVNs display a wide spectrum in morphology, such as the growth of monotonous neurocytes either in sheets, clusters, ribbons or rosettes, and neuropils dispersed in broad zones and contain a greater number of ganglion or ganglioid cells and astrocytes than CNs [5]. Furthermore, EVNs are often misdiagnosed as oligodendrogliomas, oligoastrocytomas or oligodendroglial tumors with neurocytic differentiation [6]. Immuno histo chemically, synaptophysin expression is positive and has been recognized as the most reliable diagnostic marker for identifying neuronal differentiation in brain neoplasia [7], and may thus play a vital role in the diagnosis of EVN tumors. Below we describe a rare case of sudden and unexpected death due to a clinically undiagnosed extra ventricular neurocytoma located on the midbrain.