Actinic keratosis (AK) is a common, sun-induced, pre-malignant lesion with a strong likelihood of progressing to a malignancy. The reported risk of AK progressing to squamous cell carcinoma (SCC) varies from less than 1% to 20%. Clinically, induration, pain, large size, marked hyperkeratosis, ulceration, bleeding, rapid growth, and recurrence or persistence may be markers of AK progression into...

Actinic keratoses are premalignant lesions of the skin caused by excessive sun exposure. Lesions may become mainly squamous cell carcinoma. Cryotherapy with liquid nitrogen is one of the main treatments. In order to evaluate the response of actinic keratosis to cryotherapy by histopathology, two lesions were selected in each of 14 patients with multiple actinic keratoses. In one lesion a biopsy...