Update on the diagnosis, pathogenesis, and treatment strategies for central neurocytoma.

Central neurocytomas are rare benign tumors of the central nervous system that are typically located in the lateral ventricles. Since they were first reported in the early 1980s, many advancements have been made in terms of their diagnosis and treatment. Despite the progress made, the origin of these rare tumors and effective newer treatment strategies remain elusive. Central neurocytomas represent 0.1-0.5% of all primary brain tumors. Since they are typically intraventricular, these tumors tend to present clinically with hydrocephalus. CT scanning and MRI are useful in localizing these tumors; however, due to their numerous ambiguous features, the ultimate diagnosis relies on immunohistochemistry and electron microscopy studies of sampled tissue. Currently, surgical removal with a gross-total resection of these tumors is the treatment of choice. Various radiotherapy techniques, including both conventional radiotherapy and stereotactic radiosurgery, have been shown to be useful in cases of residual tumor after sub-total resection and tumor recurrence. The benign nature of these tumors tends to offer a favorable outcome for most patients; however, recurrence rates are relatively high and tumors with high-grade features or extraventricular location tend to have a less favorable prognosis. We present a comprehensive review of these rare tumors, including their epidemiology, clinical presentation, radiological presentation, histopathological findings, and options for intervention including surgery, radiation therapy, stereotactic radiosurgery, and chemotherapy.

Neurocytoma arising in an adrenal gland mature teratoma.

Mature teratoma of adrenal gland is a rare entity. Neurocytoma is a low grade neuronal tumor even rarely seen among central nervous system tumors. Nervous system tumors arising in teratomas are frequently originated from glial or primitive neuroectodermal cells. Here we report a neurocytoma arising in mature cystic teratoma in the right adrenal gland of an 8 years old boy. Histological examination revealed a tumor composed of solid sheets in fibrillar basis with small uniform cells in the neuroglial tissue in teratoma. This is only the second case demonstrating a neurocytoma arising in a mature cystic teratoma in the literature.

Central neurocytoma expressing characteristics of ependymal differentiation: electron microscopic findings of two cases.

We describe two cases of central neurocytoma in the lateral ventricle. Ultrastructural examination showed occasional cilia mixed in with sparse dense core vesicles and thin tumor cell processes containing parallel microtubules. These central neurocytomas revealed evidence of ependymal differentiation. We propose that central neurocytoma originates from multiple differentiation from the germinal matrix cell layer.