Actinic Keratosis Appearance
Actinic keratoses initially appear as poorly defined areas of redness with telangiectasias with the skin surface becoming slightly rough. Over time, the lesions become better defined, with thin, firm, transparent scale. The scale eventually thickens, becomes adherent and turns light yellow. A well-developed actinic keratosis can sometimes be detected easier with palpation than examination. Patients will point out advanced lesions to the physician.
Lesions slowly become thicker over months or years. Hypertrophic actinic keratoses are difficult to distinguish from squamous cell carcinomas and require more aggressive treatment. Induration, inflammation, and oozing suggest degeneration into malignancy.
Occasionally, an actinic keratosis will retain scale and form an elongated keratinous structure or cutaneous horn. Warts, actinic keratosis, and squamous cell carcinoma are all capable of forming cutaneous horns. These unsightly lesions are surgically removed and examined histologically.