The following is a summary of “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,” published in the Feb 2023 issue of Dermatologic Surgery by Campbell et al.
The consensus guidelines advise against using margins smaller than 0.5 cm (in situ) and 1 cm for invasive melanoma during Mohs micrographic surgery (Mohs). However, there is limited evidence to support this recommendation. To evaluate the local recurrence rates of melanoma after Mohs surgery based on the size of the initial margin. A comprehensive systematic review and meta-analysis utilized search terms such as Mohs micrographic surgery, surgical margin, recurrent disease, and melanoma.
A total of 43 studies were incorporated. The category of margins measuring 5 to 10 millimeters demonstrated a statistically significant decrease in local recurrence when compared to the categories of 1 to 5 mm and 5 mm. The rates of recurrence for the categories of 1- to 5-mm, 5-mm, 5- to 10-mm, and 10-mm was 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. The staging for 1 to 5 mm, 5 mm, 5 to 10 mm, and 10 mm were 1.8, 1.8, 1.6, and 1.6. The study results indicate no significant difference between the groups, as evidenced by a p-value of .694. The lowest local recurrence rates were observed in cases with 5-10 mm margins. An initial margin of 5-10 mm is recommended, provided other factors such as tumor characteristics and anatomical or functional considerations permit.