Actinic keratoses (AKs) are dry, scaly, rough-textured patches or lesions that form on the outermost layer of the skin after years of exposure to ultraviolet (UV) light, such as sunlight. These lesions typically range in color from skin-toned to reddish brown and in size from that of a pinhead to larger than a quarter. Occasionally, a lesion grows to resemble an animal horn and is called a “cutaneous horn.”
It is important that anyone with AKs be under a dermatologist’s care. AKs are considered the earliest stage in the development of skin cancer and have the potential to progress to squamous cell carcinoma, a type of skin cancer that can be fatal. Anyone who develops AKs has extensive sun-damaged skin. This makes one more susceptible to other forms of skin cancer, including melanoma. Melanoma is considered the most lethal form of skin cancer because it can rapidly spread to the lymph system and internal organs.
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