Definition: Actinic keratosis (AK) (also called "solar keratosis") is a common precancerous skin condition caused by excessive exposure to ultraviolet light. AKs are rough, dry, tan- or pink-colored blemishes that often appear on facial skin -- near the eyes, on the nose, on the ears, or the lips -- or other parts of the body that receive intense sunlight, such as the back of the hands. They are most common in fair-skinned, middle-aged or elderly individuals, who may have a single lesion or many.
Actinic keratosis can lead to more serious invasive squamous cell carcinoma (SCC) if left untreated. It is estimated that 20-40% of SCCs begin as actinic keratosis. In fact, some doctors believe that AK is actually an early stage of squamous cell carcinoma. Treatments include cryosurgery (freezing), surgical excision (removal), curretage (scraping), photodynamic therapy, or topical (skin-only) creams such as fluorouracil, diclofenac, and imiquimod. The choice of treatment depends on the location of the lesion, how many there are, and the choice of the patient.
A gallery of photographs of actinic keratosis is available to help you identify them.
Also Known As: sun spots, solar keratosis, AK
Common Misspellings: aktinic keratosis
