Clinicopathological experience with intraventricular neurocytomas.

Intraventricular neurocytoma is a rare clinicopathological entity that has been recently described. We are reporting our experience with four diagnosed cases and the previously reported cases from the available literature are reviewed. These neoplasms occur mainly in young adults, and their histological diagnosis is difficult on light microscope, because they are almost indistinguishable from oligodendrogliomas. Nevertheless, the presence of tumoral cells arranged around nucleus-free fibrillary zones, resembling the large rosettes of pineocytomas and the immunohistochemical demonstration of synaptophysin are useful data for the pathological diagnosis. This diagnosis is easy on electron microscope, because it demonstrates the neuronal nature of tumoral cells. Regarding prognosis, we have found increasing evidence that these tumors are associated with a favourable course after surgery, and at present there is no clear evidence of the usefulness of radiotherapy.