Topical 5% Imiquimod in the Treatment of Lentigo Maligna

Abstract

Background: Standard treatment for lentigo maligna (LM) is surgical excision with 5 to 10 mm margins. This can be cosmetically disfiguring. Imiquimod locally induces Toll-like receptors to release cytokines that destroy neoplastic melanocytes. Objective: The off-label use of topical 5% imiquimod cream may provide an alternative to surgery. This study reviews the use of imiquimod to treat LM. Methods: A 5-year retrospective and prospective chart analysis was conducted. Pretreatment biopsies confirmed the diagnosis. Treatment was individualized for each patient. Posttreatment biopsies and dermoscopy determined clearance of LM. Results: Twenty-seven patients were reviewed. There were 20 responders (74.1%) and 7 failures. The mean tumor size (area of an ellipse) was 6.69 cm2, and the mean treatment duration was 17.68 weeks. Neither the size of the tumor ( p = .86) nor treatment duration ( p = .18) was related to resolution of the lesion. Conclusion: Imiquimod is an effective treatment for LM that provides patients with a cosmetically favorable outcome when standard surgery is not an option.