0.5% 5-Fluorouracil/10% Salicylic Acid for the Treatment of Distal Actinic Keratoses Under Daily Practice Conditions.

Background: Actinic keratosis (AKs) are sun-induced skin lesions that are at risk to progress to invasive squamous cell carcinoma (SCC). Treatments have shown to be effective on face or balding scalp area but limited data support their efficacy on distal extremities. Objective: To describe the efficacy of 0.5% 5-fluorouracil/10% salicylic acid (5FU/AS) in the treatment of distally-located AKs in daily clinical practice. Additional objectives were to review tolerance and adherence to this treatment. Methods: Retrospective review of 23 patients with distal grade II to III AKs who were treated with 5FU/AS under daily practice conditions. Primary endpoint included local skin response according to percentage on AKs reduction at week 20 (8 weeks after ending the treatment). Results: 75% (30/40) treatment areas showed a percentage reduction in AKs from to 75% to 100% at week 20. Complete response (100% clearance) was recorded in more than half of the cases (53%, 21/40). Good, partial, and low responses were respectively observed in 22% (9/40), 20% (8/40), and 5% (2/40) of patients. Most adverse events were graded as low, and adherence to treatment was considered correct in 25 patients (63%). In addition, a correct adherence to treatment was significantly related to a better response (P=0.001). Conclusion: Findings indicate that topical 5FU/AS is an effective treatment for multiple distal AKs, with a proper safety profile. J Drugs Dermatol. 2019;18(3):285-288.