Treatment of lentigo maligna with imiquimod cream: a long-term follow-up study of 10 patients.

Background: The first choice of treatment for lentigo maligna (LM) is excision. Initial studies of treatment with imiquimod 5% cream have shown promising results with excellent cosmetic outcome, but the follow-up duration in these studies was short.

Objectives: To evaluate the results of treatment of patients with LM with imiquimod in routine clinical practice with long-term follow-up.

Methods: We prospectively followed 10 patients with LM who were treated with imiquimod 5% cream between 2004 and 2007 with a median follow-up of 31 months (range 11-56 months). Histological clearance was assessed in all patients using post-treatment biopsies.

Results: Complete clinical clearance was achieved in nine of 10 patients after treatment with imiquimod. During follow-up, three clinical and histological recurrences were observed at 9, 10, and 27 months after treatment cessation. In a fourth patient, histological recurrence without clinical signs was demonstrated 17 months after treatment. Five of 10 patients are in sustained clinical remission.

Conclusions: Imiquimod appears to be an effective treatment for a subset of patients with LM. We recommend long-term follow-up and taking multiple post-treatment biopsies, even in the absence of a clinical recurrence. This case series emphasizes the need for finding an optimal treatment regimen.