Topical Chemoprevention of Skin Cancer Biomarkers

Men and women (≥ 18 yo)who have been seen as patients in the Dermatology Clinic at the University of Alabama at Birmingham with a history of basal cell or squamous cell carcinoma of the skin and at least 8 actinic keratoses on the upper extremities are potentially eligible for study participation. We propose to examine one topical medication which is already FDA approved,with a placebo comparator. The purpose of the study is to see if diclofenac applied daily will affect levels of specific biomarkers in the skin that are associated with risk of developing skin cancer. We hope to see these levels decrease with once daily use of this medication. Results from this study will help guide us in a second study where we will look at longer term use of these medications and how they are associated with changes in skin biomarkers that are related to skin cancer. The second longer study will use the dose (once or twice daily topical application of diclofenac and DMFO) that resulted in a decrease in biomarkers, as discovered in this currently proposed study.