[Cerebellar ganglioglioma associated with a huge cyst: case report].

Gangliogliomas represent approximately 0.2% of all the intracranial tumors. Ganglioglioma arising from the cerebellum is rare, with a rate of 1.5-9% of CNS gangliogliomas. The authors report a case of cerebellar ganglioglioma with a huge cyst. A 28-year-old man presented headache and ataxia. Computerized tomography (CT) demonstrated a huge cyst at the vermian region with calcification located at the peripheral side of the cyst. Magnetic resonance imaging (MRI) with administration of Gd-DTPA showed a slightly enhanced small mass at the left side of the cyst. Preoperative diagnosis of the lesion seemed to be a cystic astrocytoma. The tumor was removed subtotally through the midline suboccipital approach. Pathological examination of the tumor specimen revealed a ganglioglioma. The postoperative course was uneventful with no sign of tumor regrowth on repeated MRI. According to the previous 17 reports of cerebellar ganglioglioma including our case, the shorter interval from onset to the diagnosis and clinical symptoms such as increased intracranial pressure were conspicuous as compared with supratentorial ganglioglioma because of the anatomically narrow space of the posterior fossa. Neuroradiological findings showed tumor enhancement in 86% of the cases, calcification in 67%, and cyst formation in 53%.