“Actinic keratoses are scaly spots or patches on the top layer of skin. With time they may become hard with a wartlike surface.
Also known as a solar keratosis, an actinic keratosis grows slowly and usually first appears in people over 40. You can reduce your risk of this skin condition by minimizing your sun exposure and protecting your skin from ultraviolet (UV) rays.
Left untreated, the risk of actinic keratoses turning into a type of skin cancer called squamous cell carcinoma is about 5% to 10%.
MAYO CLINIC (Actinic keratosis – Symptoms & causes – Mayo Clinic)
“Keratoacanthoma is a dome-shaped lump or tumor that grows on your skin. Once you spot it, it’s important to talk to your doctor. It sometimes happens to people before they get squamous cell carcinoma, the second most common type of skin cancer. If you catch the problem early, treatment usually works well.”
Web MD (What is Keratoacanthoma? Causes, Symptoms, Prevention, Treatment)