Actinic keratoses (AKs) are lesions on the surface layer of the skin (epidermis) caused by chronic exposure to sunlight, particularly ultraviolet light. AKs typically manifest as rough or scaly skin, bumps, mottled patterns and cutaneous horns. They may appear anywhere on the skin surface exposed to sunlight, but common areas include the face (including ears and lips), neck, arms and hands. Lesions range in size from a pinpoint to several centimeters in diameter and may be yellow, brown, red or violet, smooth, wrinkled or furrowed.

Actinic keratoses can signal the onset of skin cancer; they can become squamous cell carcinomas, the second-most common form of epidermal skin cancer. Depending on a number of factors such as the size, location and severity of lesions, as well as the patient’s age, health, medical history, occupation, expectations and preferences, treatment for AKs may take the form of traditional surgical excision, cryosurgery (freezing), curettage (scraping), topical medications, laser treatment, chemical peels, dermabrasion and pulsed light therapy. Routine re-examinations every few months and limitation of exposure to direct sunlight are recommended.