What is a characteristic feature of actinic keratosis?

Actinic keratosis is characterized by flattened papules that have a dry, scaly surface. These lesions typically arise in sun-exposed areas of the skin, such as the face, ears, scalp, and backs of the hands, as a result of prolonged ultraviolet (UV) light exposure. The scales can be rough to the touch, and the papules are often slightly red or hyperpigmented, but they maintain a generally flat appearance.

This characteristic feature is important for identification and diagnosis, especially as actinic keratosis is considered a precancerous condition that could potentially progress to squamous cell carcinoma if left untreated. The flattened nature of these lesions, along with the presence of dry scales, helps differentiate actinic keratosis from other skin lesions, which may present with different shapes, textures, or colors. Understanding these features assists healthcare providers in monitoring and managing skin health effectively.