An actinic keratosis 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 solar keratosis, an actinic keratosis enlarges slowly and usually causes no signs or symptoms other than a patch or small spot on your skin.
Over time, actinic keratoses may develop into invasive squamous cell carcinoma; according to one study of almost 7000 patients, among the small percentage of actinic keratoses that progress into squamous cell carcinoma, the length of time for this transformation to occur was approximately 2 years.Cells within actinic keratoses (AKs) show characteristic UV-induced gene mutations.Histologically AKs share features with squamous cell carcinoma (SCC).
The risk of progression of AKs is reported in widely variable figures. Some studies estimated the risk at 0.075–0.096% per lesion per year, or about 1% over 10 years with some estimates as high as 10% over 10 years However, the Veterans Affairs Topical Tretinoin Chemoprevention Trial found that the risk of progression of AK to primary SCC (invasive or in situ) was 0.6% at 1 year and 2.57% at 4 years.
Almost all AKs can be eliminated if treated early, before they become skin cancers. Various treatment options are available, which depend on the growth’s characteristics and the patient’s age and health. Treatment can be performed in the physician’s office, and no cutting or anesthesia is required. Liquid nitrogen, applied with a spray device or cotton-tipped applicator, freezes the growths.