Dysembryoplastic neuroepithelial tumor originally diagnosed as astrocytoma and oligodendroglioma Tumor neuroepitelial disembrioplásico diagnosticado originalmente como astrocitoma ou oligodendroglioma

The dysembryoplastic neuroepithelial tumor (DNT), which was described by Daumas-Duport et al., in 19881, and it was incorporated in the World Health Organization (WHO) classification in 19932, is a benign mixed glio-neuronal tumor usually supratentorial in the cerebral cortex, which occurs predominantly in children or young adults, who present intractable complex partial seizures before 20 years-old and absence of focal neurological deficit. Radiologically, cortical topography of the lesion, no mass effect or contrast enhancement, except in a small proportion of cases, iso or hypointensity in T1-weighted and hiperintensity in T2-weighted magnetic resonance imaging (MRI) are the main features3. Histologically, it typically shows a columnar pattern and multinodular architecture, which is often associated with cortical dysplasia. There are three histological subtypes: complex, simple, and non-specific forms, which may show similarities with low-grade diffuse gliomas3. As for the ganglioglioma, which is usually benign but may recur and become anaplastic, there