Giant Cell Tumor of the Temporal Bone with Secondary Aneurysmal Bone Cyst-Like Changes and Extradural Middle Cranial Fossa Extension: A Rare Combination

Giant cell tumor (GCT) of the temporal bone is a rare, locally aggressive neoplasm. Its co-occurrence with secondary aneurysmal bone cyst (ABC)-like changes and extensive extradural extension into the middle cranial fossa (MCF) is exceptionally rare. A 24-year-old female presented with progressive left-sided conductive hearing loss and a slowly enlarging mass in the external auditory canal. High-resolution computed tomography (HRCT) revealed an expansile, erosive lesion involving the left temporal bone with extension into the external auditory canal, middle ear cavity, and mastoid air cells.