Actinic keratosis. A premalignant skin lesion.

The actinic keratotic lesion appearing on the sun-exposed skin of the middle-aged and elderly is a common premalignant lesion that infrequently becomes squamous cell carcinoma. Generally, superficially destructive measures provide adequate therapy for this epidermal dysplastic growth. Because of the rare threat of squamous cell carcinoma, a therapeutic dilemma results. If the physician detects any signs of malignancy, such as palpability, induration, or bleeding, a biopsy is mandatory for confirmation.