We present a case of primary benign intraosseousmeningioma in the sphenoid bone mimicking malignancy. A44-year-old female patient who had a protruding right eye andheadache came to our hospital. MRI showed a large, destructive,heterogeneously well-enhancing soft tissue mass in theright sphenoid bone suggesting malignancy. 18F-FDG PET/CT showed a hypermetabolic mass in the same site with anSUVmax of 9.1 The pathological diagnosis by surgery revealedthat this tumor was a WHO grade I transitional meningioma.
This case suggests that primary benign intraosseous meningiomamay show high 18F-FDG uptake mimicking amalignancy.