Local Recurrence Rates of Malignant Melanoma After Mohs Micrographic Surgery Are Lowest With 5- to 10-mm Initial Margins: A Systematic Review and Meta-Analysis

Abstract

BACKGROUND Current consensus guidelines have discouraged the use of sub-0.5-cm (in situ) and sub-1-cm (invasive) margins when performing Mohs micrographic surgery (Mohs) for melanoma, with minimal evidence to guide this recommendation. OBJECTIVE To compare melanoma local recurrence rates after Mohs based on initial margin size. MATERIALS AND METHODS A systematic review and meta-analysis was conducted with search terms including Mohs micrographic surgery, surgical margin, recurrent disease, and melanoma. RESULTS Forty-three studies were included. The 5- to 10-mm margin category had a statistically significant lower local recurrence compared with 1- to 5-mm and 5-mm categories. Recurrence for 1- to 5-mm, 5-mm, 5- to 10-mm, and 10-mm categories were 2.3% (CI 0.8–3.5, p < .001), 1.4% (CI 0.6–2.2, p < .001), 0.3% (CI 0.2–0.5, p < .001), and 6.1% (CI -6.7 - 18.8, p = .349), respectively. Number of stages for 1 to 5, 5, 5 to 10, and 10-mm categories were 1.8, 1.8, 1.6, and 1.6, respectively. There was no statistically significant difference between the groups (p = .694). CONCLUSION Five- to 10-mm margins were associated with the lowest local recurrence rates. A 5- to 10-mm initial margin should be considered where other factors (tumor characteristics, anatomical or functional considerations) allow.

Disease-specific survival of malignant melanoma after Mohs micrographic surgery is not impacted by initial margins: A systematic review and meta-analysis

“…When selecting an initial surgical margin, there are numerous factors to take into consideration. In a previous study conducted by our team, the local recurrence rates of melanoma were analyzed based on the initial margin size, 11 discovering that the lowest local recurrence rates were associated with initial margins ranging from 5 to 10 mm. Consequently, it was recommended to consider an initial margin of 5 to 10 mm, provided that other factors such as tumor characteristics, anatomical or functional considerations permit.…”

“…To our knowledge, there is no previous literature comparing surgical outcomes of melanoma after MMS based on initial margin size, aside from a similar paper published by our group which analysis local recurrence after MMS based on initial margin. 11 In this study, a systematic review and meta-analysis was conducted to compare the disease-specific survival rates of malignant melanoma after MMS based on initial margin.…”

From Centimeters to Millimeters: The Evolution of the Surgical Margins for Melanoma—A Historical Review

“…Specifically, the investigators emphasized that recurrence rates were lowest when 5 to 10-mm margins were used, compared with 1 to 5-mm margins ( p < .001). 20 The ability to confidently assess 100% of the deep and peripheral histologic margin likely underlies the superior clinical outcomes seen with MMS compared with standard bread loafing of permanent fixed tissue, which examines only 1% of excised tissue margins.…”