Mohs micrographic surgery in the treatment of lentigo maligna and melanoma

Abstract

Background and objectives: The treatment of lentigo maligna (LM) and lentigo maligna melanoma (LMM) is challenging due to lesion location, size, patient age, and potential for recurrence and spread. The largest studies to date confirm that for melanocytic tumours, MMS provides high local control rates while minimizing tissue loss. Herein we report our local control rate for melanoma treated by MMS over a decade.

Methods: Charts were reviewed on all patients with melanocytic tumors treated by a single physician (JPA) using MMS over the time period of 1993-2002. Demographic, surgical and pathological details were recorded. Patients were followed for local, regional and distant recurrences.

Results: The patient population was comprised of 199 patients with 202 melanomas. There were 69 invasive lesions, with a mean Breslow depth of 0.92 mm (0.2-3.6 mm). The mean number of levels required to clear the lesions was 2.7 (1-7), resulting in a mean defect size of 11.8 cm2 (0.9-70.7 cm2). Patients with LMM were significantly older (73.2 vs. 66.5 yrs, p = 0.012) and had larger defects after MMS (16.74 cm2 vs. 10.27 cm2) than patients with LM. At a mean follow-up of 29.8 months, there were no local recurrences, four regional recurrences, and two distant recurrences.

Conclusion: MMS is an effective modality for the clearance of melanocytic tumors.