[A rare primitive neuroectodermal tumor: the medulloepithelioma].

Primitive neuroectodermal tumors (PNET) is a name used to describe rare and highly malignant tumors composed of undifferentiated cells resembling germinal or matrix cells of the embryonic neural tube. These tumors occur most commonly in the first decade of life, and have a particular radiological, histological and evolution features. We report a case of a PNET in an 8-year-old boy who presented intracranial hypertension studied with computed tomography scan, which demonstrated a sharply circumscribed expansive mass in the frontoparietal deep white matter, with a large cystic component, which was considered at first as a glial tumor. It was treated by total excision, and the histologic study demonstrated a medulloepithelioma. We studied the concept of PNET and their pathological, radiological and prognostic features.