An actinic keratosis (ak-TIN-ik ker-uh-TOE-sis) is a rough, scaly patch on your skin that develops from years of exposure to the sun. It's most commonly found on your face, lips, ears, back of your hands, forearms, scalp or neck.
Also known as a solar keratosis, an actinic keratosis enlarges slowly and usually causes no signs or symptoms other than a patch or small spot on your skin. These patches take years to develop, usually first appearing in people over 40.
A small percentage of actinic keratosis lesions can eventually become skin cancer. You can reduce your risk of actinic keratoses by minimizing your sun exposure and protecting your skin from ultraviolet (UV) rays.
Nov. 09, 2016
- Goldsmith LA, et al., eds. Epithelial precancerous lesions. In: Fitzpatrick's Dermatology in General Medicine. 8th ed. New York, N.Y.: The McGraw-Hill Companies; 2012. http://accessmedicine.com. Accessed Aug. 5, 2016.
- Padilla RS. Epidemiology, natural history and diagnosis of actinic keratosis. http://www.uptodate.com/home. Accessed Aug. 5, 2016.
- Wolff K, et al. Photosensitivity, photo-induced disorders and disorders by ionizing radiation. In: Fitzpatrick's Color Atlas and Synopsis of Clinical Dermatology. 7th ed. New York, N.Y.: The McGraw-Hill Companies; 2013. http://www.accessmedicine.com. Accessed June 19, 2015.
- Actinic keratosis. American Academy of Dermatology. http://www.aad.org/dermatology-a-to-z/diseases-and-treatments/a---d/actinic-keratosis. Accessed Aug. 5, 2016.
- Gibson LE (expert opinion). Mayo Clinic, Rochester, Minn. Oct. 21, 2016.
- Jorizzo J. Treatment of actinic keratosis. http://www.uptodate.com/home. Accessed Aug. 5, 2016.
- FDA sheds light on sunscreens. Food and Drug Administration. http://www.fda.gov/forconsumers/consumerupdates/ucm258416.htm. Accessed Aug. 5, 2016.
- AskMayoExpert. Actinic keratosis. Rochester, Minn.: Mayo Foundation for Medical Education and Research; 2016.
- Habif TP. Light-related diseases and disorders of pigmentation. In: Clinical Dermatology: A Color Guide to Diagnosis and Therapy. 6th ed. Maryland Heights, Mo.: Elsevier; 2016. http://www.clinicalkey.com. Accessed June 19, 2015.
- Sunscreen FAQs. American Academy of Dermatology. https://www.aad.org/media/stats/prevention-and-care/sunscreen-faqs. Accessed Sept. 26, 2016.
- Lebwohl M. Actinic keratosis. JAMA. 2016;315:1394.