You can think of an AK lesion as a marker for an area of the skin that is at higher risk for turning into a skin cancer (primarily squamous cell carcinomas) than the surrounding skin.
Studies have proven that skin with actinic keratoses is at greater risk of developing skin cancer. Some of the best clinical studies were published in Australia where the skin cancer rates are very high.
The is the same thing that is happening with polyps of the colon that are at risk of developing into colon cancer. These colonic polyps are identified and removed…..but identifying and treating actinic keratoses is easier than a colonoscopy.
Sunscreen and sun protective clothing will help prevent the growth of AKs, though most people got most of their exposure when they were younger. Nonetheless, clinical studies have demonstrated that regular sunscreen use and sun protection will lower the occurrence of new actinic keratoses, even in those people who already have many.