Topical colchicine therapy for actinic keratoses

Background: The beneficial effect of topical colchicine therapy for actinic keratoses has already been described in 1968. Objective: To confirm that the application of a 1% colchicine gel is a safe and effective treatment for actinic keratoses. Methods: Twenty patients were included in a double-blinded protocol. They all had actinic keratoses on the scalp, most of which had been previously treated with 5-fluorouracil or cryotherapy. Ten patients applied twice daily on the forehead a hydrophilic gel (placebo group), while the other 10 where treated with the same gel containing 1% of colchicine (colchicine group). Erythema and efficacy were evaluated at each control on days 7, 30 and 60, with repetitive blood tests to exclude a possible systemic absorption. Results: A complete healing of the solar keratoses was observed in 7 out of the 10 patients treated with 1% colchicine gel; these showed no recurrence after 2 months of follow-up. Burning and itching occurred only in the colchicine group after 2 or 3 days of application, with an inflammatory reaction on the areas where the gel was applied, while pustules and crusts were located specifically on the actinic keratoses. Repealed blood controls showed that there was no systemic absorption. Conclusions: This double-blind placebo-controlled study confirms the activity of colchicine for the treatment of actinic keratosis. A comparison with other topical treatments in terms of efficacy and practicability is needed. Copyright (C) 2000 S. Karger AG, Basel.