Abstract

Keratoacanthomas are cutaneous keratin-plugged nodules that spontaneously occur from the pilosebaceous unit, rapidly grow, and generally regress. The peak incidence of solitary keratoacanthoma occurs between 50 and 69 years of age. Risk factors include but are not limited to exposure to ultraviolet light, trauma, human papillomavirus, and immunosuppression. Although they occur more often in sun-exposed areas like the face, there are several situations, such as the present case, where they may occur in less-exposed areas such as the legs and buttocks. As a result, merely being aware of risk factors and undergoing a purely physical examination is insufficient to distinguish this from other skin cancers.