Meningioma: a typically benign brain tumor although up to 5% can be aggressive or malignant. They are more common in women than men and can occur in all ages but are typically seen in middle-aged and older adults. Meningiomas may arise from any meningeal surface and are typically attached to the dura (outer layer of the meninges). Common locations include the convexity of the calvarium, frontal fossa (olfactory groove), tuberculum sella (near the pituitary gland), sphenoid wing and in other skull base areas. Primary treatment of symptomatic meningiomas is usually by surgical removal, often by a keyhole craniotomy or endonasal approach. Learn more.