Lipomatous meningioma: A rare subtype of benign metaplastic meningiomas.

Lipomatous meningiomas are extremely rare subtypes of benign meningiomas and are classified as metaplastic meningioma in the World Health Organization classification. We present a 77-year-old man presented with the history of a gradually intensifying headache for the last 3 months. A right frontoparietal mass was detected on his cranial magnetic resonance imaging. The patient was operated on via a right frontoparietal craniotomy, and histopathological diagnosis was lipomatous meningioma. Distinctive characteristics of lipomatous meningiomas were discussed with special emphasis to importance of immunohistochemical examinations, particularly for its differentiation from the tumors showing similar histology though having more aggressive character.