Topical 5% imiquimod in the treatment of lentigo maligna.

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.