Mohs micrographic zurgery versus wide local excision for the treatment of melanoma in situ

Summary: Abstract Body: The treatment of melanoma in situ (MIS) presents a unique challenge due to the frequent amelanotic spread of tumors arising from the head and neck as well as presentation in cosmetically sensitive areas. Although wide local excision (WLE) is the current standard of care for MIS, Mohs micrographic surgery (MMS) is increasingly being used due to the confirmation of tumor clearance using histopathologic examination of surgical margins and the tissue-sparing approach. This systematic review of the literature evaluates MMS versus WLE in the treatment of MIS. Eligible articles were identified using PubMed, EMBASE, and Cochrane Library. 11 studies were included. Five studies directly assessed the efficacy of WLE versus MMS, five studies assessed MMS only, and one study assessed WLE only. Overall, MMS was similar to WLE regarding both survival and MIS recurrence. Of the three studies that compared survival between WLE and MMS, all reported no statistical difference between the 5, 10, or 15-year survival rates. One study evaluated survival after MMS only and reported zero melanoma-related deaths after a follow-up period ranging from 3 to 30 months. Regarding recurrence rate, the two studies directly comparing WLE and MMS both reported a greater but non-significant rate of recurrence from WLE versus MMS. From the eight studies that evaluated recurrence after MMS, the rate of recurrence ranged from 0% to 17%; however, only one study reported a recurrence rate above 5%. From the four studies that evaluated recurrence after WLE, the rate of recurrence ranged from 0% to 7.3%. One study reported that recurrence after WLE was 3.6 times greater than MMS (95% confidence interval 0.220 - 0.683, P = 0.0008). Overall, WLE cases resulted in similar rates of survival but higher rates of MIS recurrence compared to MMS. MMS is a reasonable option for MIS excision in anatomic locations where tissue sparing is important. Joycie Chang¹, Grace Steinback¹, Anand Rajpara¹ 1. Dermatology, University of Missouri - Kansas City School of Medicine, Kansas City, MO, United States. Pigmentation, Melanoma, and Melanoma Immune Surveillance