Metaplastic meningioma with pure and extensive cartilaginous transformation: A diagnostic dilemma

Abstract

Meningiomas are the most common extra-axial central nervous system tumours and often discovered in the middle to late adult life and especially in women. About 85%-90% of meningiomas are benign, 5%-10% are intermediate-grade, and 3%-5% are malignant. Metaplastic meningioma is a rare subtype of WHO Grade I meningioma histologically characterized by the presence of mesenchymal components. The presence of pure and extensive cartilaginous differentiation in meningiomas is extremely rare and remains a diagnostic dilemma. We report, perhaps the first case of this entity in a 52-year-old woman and discuss the pathogenesis, the imaging features and the histopathologicals data.