I only saw one scaly dry area on temple & then Doctor said actinic keratosis and another spot on nose. How can Dr. See this and what is Diffuse AK?

Actinic keratoses. Actinic keratoses are small scaly patches of skin usually seen on the face and usually only on ageing skin (more common after age 50). These lesions are pre-malignant and is large enough should be removed. The doctor usually makes this diagnosis by viewing the lesions and then biopsying them. Diffuse actinic keratoses (diffuse AK) is a condition where there are multiple AK lesions on the body.