Epidermal cyst of the skin with ossification: report of two cases.

Epidermal cyst of the skin, also referred to as epidermoid or infundibular cyst, is a common benign cystic lesion and is thought to occur from damage to the pilosebaceous units [1]. This kind of lesion is unilocular, histopathologically lined by a stratified squamous epithelium containing a granular layer, and filled with laminated and/or basket-weave keratin within the cyst, which is believed to represent follicular infundibular derivation [1]. It is not uncommon for it to be accompanied by acute inflammation, leading to the disruption of the cyst wall, with the development of foreign body reaction.