Stages of skin cancer are a little bit different than stages of let's say, breast cancer or colon cancer. It's best to think of them as normal moles, dysplastic moles, which are precancerous, and melanoma, which is a type of cancer. Dysplastic moles or nevi, are easily treated with a simple excision.
If we let them grow they can turn into melanoma, which will require more extensive excision, and depending on the depth of invasion, lymph node dissection or chemotherapy. Basal and squamous cell carcinomas are a little bit easier to understand, as they tend to not to invade or metastasize.
Actinic keratosis are considered the precancerous lesions that can lead to squamous cell carcinoma. The rate of transformation from actinic keratosis to squamous cell carcinoma is controversial.
Studies infer anywhere, from between less than 1.0% to 10% transformation into skin cancer. If you are diagnosed with actinic keratosis, it's important to talk to your dermatologist to find out about the latest research, and determine what kind of treatment is necessary for you.