Extraventricular Neurocytomas

Abstract

Extraventricular neurocytomas (EVNs) are rare neoplasms with many similar morphologic features compared with central neurocytomas. EVNs have been reported in a variety of locations and mainly occur within the cerebral hemispheres. These lesions display wide variability in morphologic features, cellularity, and proliferation rates. In addition, given their aggressive biological nature and tendencies to affect eloquent areas, EVNs are associated with a poorer prognosis. The epidemiology of these rare tumors is not definitively known, and effective treatment strategies have not been developed. This article reviews these tumors, including their epidemiology, clinical presentation, locations, radiological findings, treatment options, and prognosis.

Malignant progression of an extraventricular neurocytoma arising from the VIIIth cranial nerve: A case report and literature review

“…Neurocytoma can also occur in brain parenchyma, or even in sites remote from the ventricles. Therefore, the latter tumor was named EVN . Histopathologically, both CN and EVN display uniform, small, round cells with clear cell cytoplasm in a neuropil background .…”

“…EVNs also display a histological resemblance to oligodendrogliomas. In adults, EVNs are most likely to occur within the frontal lobe, followed subsequently by the temporal lobe, parietal lobe and occipital lobe . However, examining previous publications, only one report of EVN in association with the VIIIth cranial nerve has been described .…”

“…CN is a low‐grade neoplasm that is characterized by its intraventricular localization, its occurrence predominantly in young adults, its histological resemblance to oligodendrogliomas, and its expression of neuronal markers . Shortly after the establishment of CN, similar tumors of the central nervous system were reported in several locations outside the supraventricular system as extraventricular neurocytomas (EVNs) . Histologically, EVN is an unusual tumor that is histologically composed of small uniform cells that demonstrate neuronal differentiation.…”

Clinical characteristics and prognostic factors of brain central neurocytoma

“…CN typically located in deep midline structures near the foramen of Monro, such as the third ventricle or the anterior portion of the lateral ventricle [3, 8]. but there were also some rare cases of extraventricular neurocytoma reported in other locations, such as spinal dissemination [19–22]. Surgery was the primary initial treatment for CN [23–25], but whether complete resection surgery correlates significantly with overall survival was still disputed [8, 24, 26, 27].…”

Different Central Localizations, Different Histopathologies, Benefits, and Side Effects of Radiotherapy in Neurocytoma

“…[37] The most common symptoms are psychosification of 2007. [19][20][21] Extraventricular neurocytoma is a very rare tumor and it is only presented as case report or in small series in the literature. There is very limited data about clinical findings, radiological features, management, or prognosis of extraventricular neurocytoma.…”