Intracerebral primitive neuro-ectodermal tumor (PNET).

A case of intracerebral primitive neuro-ectodermal tumor (PNET) is presented. PNETs are rare, undifferentiated neoplasms occurring primarily in children and young adults. These tumors exhibit a highly malignant behaviour with a tendency to disseminate along the cerebrospinal fluid (CSF) pathways. Preoperative diagnosis is difficult, owing to the non-specific CT and MR appearances and to the rarity of this tumor. Our patient was 33 years old, which is uncommon. CT findings initially suggested an intracerebral hematoma. Later on, CT and MR findings were specific for a brain tumor and showed a solid, non-calcified invasive mass, with poor perilesional edema.