What is an actinic keratosis?

An actinic keratosis (AK) is a precancerous skin growth that appears on areas of the skin that have received chronic sun exposure. They appear as small rough spots on the skin that can range in size from the size of a pencil point to the size of a quarter. They are usually pink to red in color; however, they can also appear yellowish, brownish, or whitish. Often you may feel these spots before you see them, and they are often surrounded by evidence of sun damage, including enlarged blood vessels and wrinkling or yellowing of the skin. Eventually actinic keratoses become rougher and more crusted, and they can become sore or painful to the touch. A cutaneous horn is a special type of actinic keratosis which protrudes from the skin in a thick, horn-like manner. Actinic cheilitis refers to precancerous damage of the lip, and it appears as a rough, scaling spot on the lower lip.