Five-year outcomes of wide excision and Mohs micrographic surgery for primary lentigo maligna in an academic practice cohort.

BACKGROUND: Wide local excision with 5-mm margins is the standard of care for lentigo maligna (LM). Mohs micrographic surgery (MMS) is used increasingly to treat this tumor.

OBJECTIVE: To study the authors' experience with these 2 approaches.

MATERIALS AND METHODS: Primary LM cases treated at the authors' institution from January 1, 1995, through December 31, 2005, were studied retrospectively. Main outcome measures were recurrence and outcomes after treatment for recurrence.

RESULTS: In total, 423 LM lesions were treated in 407 patients: 269 (64%) with wide excision and 154 (36%) with MMS. In the MMS group (primarily larger head and neck lesions with indistinct clinical margins), recurrence rates were 3 of 154 (1.9%). In the wide excision group (primarily smaller, nonhead and neck, or more distinct lesions), recurrence rates were 16 of 269 (5.9%). Each of the 16 recurrences was biopsy proven and treated surgically: 6 by standard excision and 10 by MMS.

CONCLUSION: This follow-up study of LM surgical treatments shows excellent outcomes for wide excision and MMS. Because this is a nonrandomized retrospective study, no direct comparisons between the 2 treatments can be made. When recurrences occurred, repeat surgery, either standard excision or MMS, was usually sufficient to provide definitive cure.