A Frontal Giant Intradiploic Giant Pearl (Epidermoid Cyst) With Intracranial and Extracranial Extension: A Rare Entity.

Craniofacial epidermoid cysts are rare tumors representing 0.2%-1% of all the intracranial tumors. Intradiploic variants account for 25% of these cysts. These cysts are benign, slow-growing, congenital tumors derived from ectodermal remnants misplaced during embryogenesis. Mean age at presentation of these lesions is 40 years; epidermoid cysts are typically asymptomatic (Toglia JU, Netsky MG, Alexander E Jr. Epithelial (epidermoid) tumors of the cranium. Their common nature and pathogenesis. J Neurosurg 1965;23:384-93). Giant extradural epidermoid cysts with profound deformation of the brain and extensive lytic skull lesions may allow a normal life without any significant neurological deficits. Computed tomography scan and magnetic resonance imaging play an important role in the diagnosis of the lesion and management protocol. Histologically, epidermoid cysts are lined by stratified squamous epithelium and are filled with anucleatic keratin (Hao S, Tang J, Wu Z, Zhang L, Zhang J, Wang Z. Natural malignant transformation of an intracranial epidermoid cyst. J Formos Med Assoc 2010;109:390-6). Complete removal of the cyst along with its capsule is the treatment of choice. Recurrences of intradiploic epidermoid cyst have been reported. Here, we report a case of 14-year-old girl presenting with a giant frontal intradiploic epidermoid cyst with an intracranial and extracranial extension without any neurological deficits. Bifrontal craniotomy was performed and cyst was excised in toto.