[A case of lipomatous meningioma]

We present a case of a 55-year-old woman with intracranial lipomatous meningioma attached to the left sphenoid ridge. A CT showed a mass lesion partially with a hypodensity area in the left fronto-temporal lobe. On MRI, the mass lesion contained a hyperintensity portion on T1 weighted images, which changed to hypointensity on fat-suppressed-T1 images. Histological examinations demonstrated a transitional meningioma containing lipomatous portions. Immunohistochemical studies showed negative reactivity for epithelial membrane antigen (EMA) and positive reactivity for vimentin and S-100 in the areas with lipomaous foci. This pattern of reactivity was different from that of lipomatous meningiomas reported previously. Further examinations are needed concerning the origin of tumor cells in lipomatous meningiomas.