Comparing efficacy and safety of potassium hydroxide 5% solution with 5-fluorouracil cream in patients with actinic keratoses: a randomized controlled trial

Background: Actinic keratosis (AK) is a pre-cancerous skin lesion, associated with development of squamous cell carcinoma. Current treatment options are limitedObjectives: To compare the efficacy and safety of topical 5-fluorouracil cream (5-FU) and potassium hydroxide 5% (KOH) in the treatment of AK.Methods: Eighteen patients with AK applied KOH solution or 5-FU on each side of their scalp/face, randomly. The efficacy and safety of these treatments were compared.Results: Thirteen (118 lesions) and ten (83 lesions) patients were successfully followed for one and three months, respectively. After one month, KOH showed a better clinical response (81% vs. 58%; P-value =0.007) and dermoscopic response (KOH, 65% vs. 5-FU, 46%; P-value =0.04); while no differences were noted after three months (clinical response, 83% vs.70%, P-value =0.1; dermoscopic response, 76% vs. 59%, P-value =0.1). No significant differences in the recurrence rate of the lesion between the two groups were noted at the end of the third month (P-value =0.5). Regarding the safety of the treatments, the risk of developing erythema, scaling, sand swelling was higher in 5-FU group (P-value <0.0001, for all), while more patients in KOH group had erosion and ulcer (P-value <0.001 for both). KOH was up to 96% less expensive than 5-FU.Limitations: Low number of patients and short-term follow-up limited the analysis.Conclusion: KOH solution offers a faster and less expensive resolution of AK lesions than does 5-FU.Ethics approval number: IR.TUMS.TIPS.REC.1397.010 (the Pharmaceutical Sciences Research Institute of Tehran University of Medical Sciences' ethics committee)Clinical Trial Code (IRCT.ir): IRCT20180909040978N1.

Keywords: 5-Fluorouracil; Actinic keratosis; potassium hydroxide.