Epidermoid Cyst of the Lower Lip: a Case Report

Kaohsiung J Med Sci October 2005 • Vol 21 • No 10 475 Epidermoid cysts can be classified as either congenital or acquired [1]. Congenital types are thought to develop from congenital inclusions of ectodermal tissue during embryologic development, whereas acquired variants are believed to originate through implantation of epithelium, by either surgical or accidental trauma into deeper mesenchymal tissues [1]. Congenital and acquired varieties of epidermoid cysts cannot be differentiated microscopically or histopathologically. In both types, the wall of the keratinfilled cyst is lined by keratinizing stratified squamous epithelium, lacking skin appendages in the cystic wall [1]. Mucoceles are typically the result of traumatic damage to a duct and obstruction to the drainage of a minor salivary gland [2]. Whereas both acquired (implantation-type) epidermoid cysts and mucoceles have been described individually in the literature [1,2], their concomitant occurrence has not yet been documented, either at the same site or at different locations. Herein, we report on an uncommon and interesting case of simultaneous epidermoid cyst and mucocele occurrence in the lower labial mucosa. CONCURRENT EXTRAVASATION MUCOCELE AND EPIDERMOID CYST OF THE LOWER LIP: A CASE REPORT