Effect of a one-week treatment with 0.5% topical fluorouracil on occurrence of actinic keratosis after cryosurgery. A randomized, vehicle-controlled clinical trial

Journal of Drugs in Dermatology, Sept-Oct, 2004

The authors set forth to determine the six-month outcome of a one-week course of 0.5% fluorouracil followed by cryosurgery for the treatment of actinic keratosis (AK). The study is double blinded, prospective, multicenter, randomized, and vehicle-controlled.

A total of 144 patients with five or more visible or palpable actinic keratoses on the face were enrolled were given vehicle or topical 0.5% fluorouracil or vehicle once daily for seven days. The follow-up visit was done at four weeks and residual lesions were treated with cryosurgery.

The authors documented a reduced mean actinic keratosis lesion count at four weeks. The lesion count was reduced by 62.4% in the 0.5% fluorouracil group versus 28.8% in the vehicle group. The study demonstrates complete clearance in 16.7% of patients in the 0.5% fluorouracil group versus 0% of the vehicle group. The next follow-up visit, at six months, showed mean lesion count was reduced by 67.0% in the 0.5% fluorouracil plus cryosurgery group versus 45.6% in the vehicle plus cryosurgery group. A complete resolution was seen in 30% of patients in the 0.5% fluorouracil plus cryosurgery group versus the vehicle plus cryosurgery group, 7%.

JDD ARTICLE EVALUATION

The authors present a well-devised study with good results, albeit not as dramatic as the authors state. There is only one suggestion I would add: Why not compare topical 5-FU, cryosurgery, and vehicle alone and then in conjunction. It would of made more sense, cost-effective wise and in efficacy, to compare these product solo and possibly with imiquimod, another therapeutic option. Yet the effects of imiquimod would probably have to be seen with longer therapies.

There is only a 5% increase (62.4% to 67.0%), in the 5-FU group by adding cryosurgery. Because of this, the efficacy of cryosurgery alone in comparison would have been helpful to analyze a more cost-effective therapy. Never the less, complete resolution was in 30% of cases that were treated with the combo of cryosurgery and 5-FU but it can be inferred that cryosurgery alone could completely clear lesions in 7% of cases, vehicle and cryosurgery group.

All in all, a well prepared study lacking a cost analysis, but better results are obtained when cryosurgery and 5-FU are used in combination.

Jorizzo J, et al. Arch Dermatol 2004: 140:813-6.