Clear Cell Meningioma

ABSTRACT

Clear cell meningioma is a recently recognized morphologically unique entity. It shows no sex predilection, affects primarily the lumbar region, and the cerebellopontine angle. Despite its benign appearance, it may be aggressive, particularly in intracranial cases. All lesions are moderately cellular, with the exception of stromal hyalinization. The tumor consists largely of a sheet- like or somewhat lobular pattern of polygonal cells, the cytoplasm of which is clear. No close association is noted between the recurrence or the clinical outcome and factors such as mitotic activity, the PCNA index, and the DNA ploidy status. But the MIB-1 proliferation index is appreciably higher in recurrent tumors. We experienced a case of clear-cell meningioma showing a characteristic histologic finding. A 39-year-old man was admitted due to the recent onset of right-sided, facial-nerve palsy, left hemiparesis and general weakness. A CT scan of the head showed a well defined mass in the petroclival area. After surgical resection, the patient was in good condition, but 1 year later symptoms recurred. A CT scan of the head showed a huge, recurrent petroclival tumor with adhesion to the surrounding brain parenchyme.