Mohs micrographic surgery for melanoma: A prospective multicenter study

Single-institution studies show that frozen section Mohs micrographic surgery (MMS) is an effective treatment modality for cutaneous melanoma, but no multi-institutional studies have been published. To characterize the use of MMS in the treatment of melanoma at 3 academic and 8 private practices throughout the United States, to recommend excision margins when 100% histologic margin evaluation is not used, and to compare actual costs of tumor removal with MMS vs standard surgical excision. Prospective, multicenter, cohort study of 562 melanomas treated with MMS with melanoma antigen recognized by T cells 1 immunostaining. Primary trunk and extremity melanomas (noninvasive and invasive melanoma) achieved histologically negative margins in 97% of tumors with 10-mm margins, whereas 12-mm margins were necessary to achieve histologically negative margins in 97% of head and neck melanomas. Overall average cost per tumor treated was $1328.46. Nonrandomized and noncontrolled study. MMS with melanoma antigen recognized by T cells 1 immunostaining safely provides tissue conservation and same-day reconstruction of histologically verified tumor-free margins in a convenient, single-day procedure. When comprehensive margin evaluation is not used, initial surgical margins of at least 10 mm for primary trunk/extremity and 12 mm for head/neck melanomas should be used to achieve histologically negative margins 97% of the time.