Treatment monitoring of 5-fluorouracil 0.5%/salicylic acid 10% lesion-directed therapy for actinic keratosis using dermoscopy and in-vivo reflectance confocal microscopy

Recently, 5-fluorouracil 0.5%/salicylic acid 10% (5-FU/SA) topical solution has been included in the National Italian portfolio for lesion-directed treatment of grade I/II actinic keratosis (AKs) located on the face or scalp. To describe the utility of dermoscopy and RCM in treatment response monitoring of a series of AKs treated with 5-FU/SA as lesion-directed therapy. Consecutive patients were prospectively treated for a maximum of 12 weeks with 5-FU/SA for AKs located on the face or scalp. Clinical, dermoscopic, and confocal images of one index AK were acquired at each visit and pre-specified criteria were evaluated. Clinical, dermoscopic, and confocal responses were evaluated at last follow-up visit. Fourteen patients were enrolled, of which five were treated for 12 weeks, seven for 8, and two for 4 weeks. At a median follow up of 30 weeks, 64.3% (9/14) index AKs achieved complete clinical, 50% (7/14) complete dermoscopic and 42.9% (6/14) complete confocal clearance. Local skin reaction was mild and significantly decreased during therapy administration. Although the small number of cases, our study underlines the utility of both dermoscopy and in-vivo RCM in 5-FU/SA treatment response monitoring for AKs located on the face or scalp.