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 limited. Objectives 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.