Atypical extraventricular neurocytoma.

Department of Neurosurgery, Cancer Research Institute, Ischemic/Hypoxic Disease Institute, Seoul National University College of Medicine, Seoul, Korea.
Journal of Korean Neurosurgical Society (Impact Factor: 0.6). 10/2011; 50(4):381-4. DOI: 10.3340/jkns.2011.50.4.381
Source: PubMed

ABSTRACT The authors report a case of atypical extraventricular neurocytoma (EVN) transformed from EVN which had been initially diagnosed as an oligodendroglioma 15 years ago. An 8-year-old boy underwent a surgical resection for a right frontal mass which was initially diagnosed as oligodendroglioma. When the tumor recurred 15 years later, a secondary operation was performed, followed by salvage gamma knife treatment. The recurrent tumor was diagnosed as an atypical EVN. The initial specimen was reviewed and immunohistochemistry revealed a strong positivity for synaptophysin. The diagnosis of the initial tumor was revised as an EVN. The patient maintained a stable disease state for 15 years after the first operation, and was followed up for one year without any complications or disease progression after the second operation. We diagnosed an atypical extraventricular neurocytoma transformed from EVN which had been initially diagnosed as an oligodendroglioma 15 years earlier. We emphasize that EVN should be included in the differential diagnosis of oligodendroglioma.

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