Cysts are asymptomatic until they become inflamed. They are among the most common skin lesions. Patients present with subcutaneous nodules that have the consistency of semifirm jelly, much like the feel of an eyeball. They are freely movable under the skin. Epidermoid cysts appear most commonly on the face, neck, upper trunk, and scrotum. They often have a visible central punctum (Fig. 43-1). Pilar cysts mainly occur on the scalp; multiple cysts are common. These cysts often lack a central punctum and are filled with keratin, which may have a slightly cheesy smell. Either type can rupture and become inflamed; frank infection with Staphylococcus aureus is less common. In either situation, the lesions become quite painful and drain serous or foul-smelling keratinaceous material.