OBJECTIVES: I. Determine the efficacy of the green tea extract epigallocatechin gallate (Polyphenon E topical ointment) in causing complete clinical and histopathologic regression in patients with actinic keratoses. II. Determine duration of treatment with Polyphenon E necessary to cause regression in these patients. III. Describe pathophysiologic and molecular alterations in actinic keratoses and sun damaged skin that are not present in skin that is not sun damaged in these patients. IV. Determine the effects of this treatment on biomarkers for skin cancer in these patients.