Excision margins for melanoma in situ on the head and neck—A single-center 10-year retrospective review of treatment with Mohs micrographic surgery

Abstract

Although current guidelines recommend a 5mm surgical margin for the excision of melanoma in situ (MIS), increasing evidence has shown this may be suboptimal to achieve tumor clearance. To evaluate margins required for optimal cure rates with excision of MIS on the head and neck and investigate tumor and/or patient factors in those requiring >5mm margins to achieve tumor clearance. A retrospective chart review was performed on 846 (807 primary and 39 recurrent) MIS cases on the head and neck treated in the authors' dermatologic surgery department over a 126-month (10.5year) period. Sixty-two percent were cleared with 5mm margins. A total of 15mm margins were required to achieve a 97% clearance rate. Difference in clearance rate between margin thresholds was significant (P<.001). Tumor location on the cheek and larger preoperative size correlated with requiring >5mm margins to achieve tumor clearance (P=.006 and P=.001, respectively). This is a single-center retrospective study which relies on accurate documentation of clinical data. This study demonstrates that MIS on the head and neck often requires margins >5mm margins to achieve tumor clearance. When Mohs micrographic surgery is not possible, excision margins of ≥10mm are likely necessary for head and neck tumors.