I've had "precancers" in the past, but never a skin cancer. What does this mean?
Actinic keratoses are often referred to as "precancer" lesions. These are often seen as small, scaly pink bumps on areas that have been exposed to the sun, such as the scalp (especially in men who have less hair protecting the skin in these areas), the face, and hands. Sometimes the scale peels off, but over time it usually returns, and the spot itself does not go away with time. Actinic keratoses are basically areas of skin that contain abnormal cells due to long-term damage from UV radiation. Over a long period of time, when untreated, these abnormal cells can eventually progress to the point that they become a type of skin cancer, namely squamous cell carcinoma. While it's difficult to say exactly what the risk is for one of these lesions to turn into a skin cancer, we estimate that over a 10-year period, there is a 1-2% chance that a single actinic keratosis will progress to squamous cell carcinoma. While this is very low, someone who has had one actinic keratosis will likely get more over time, increasing the risk over time of getting a skin cancer if these are left untreated. That is why your dermatologist will recommend treating them, often with a simple procedure called cryotherapy, where cold liquid nitrogen is sprayed directly onto the spot to destroy the abnormal cells. There are other ways of treating these as well, such as special creams, and your dermatologist can help determine which is the best method for you.