Basal cell carcinoma or BCC is the most common malignancy in humans. It is believed that BCCs arise from pluripotential cells in the basal layer of the epidermis or, less commonly, hair follicle. BCCs typically occur in areas of chronic sun exposure and present as slowly enlarging reddish papules, plaques or nodules on the head and neck, although the superficial variant is often located on the trunk. BCCs frequently ulcerate and become crusted. Although they rarely metastasize, they can cause significant local destruction and disfigurement if neglected or inadequately treated, particularly if of the sclerosing or infiltrative subtype.