A prospective study evaluating the utility of a 2-mm biopsy margin for complete removal of histologically atypical (dysplastic) nevi.

Background: Complete removal of individual dysplastic nevi (DN) is often accomplished by a second surgical procedure after the initial biopsy. The choice to perform the second procedure is strongly influenced by histopathologic margin status of the initial biopsy specimen.
Objective: To evaluate the clinical and histopathologic outcomes of in toto biopsy of DN using a predetermined margin of normal skin.
Methods: We conducted a prospective study of a saucerization method using a defined 2-mm margin in patients undergoing biopsy of a pigmented skin lesion.
Results: We performed 151 biopsies in 138 patients. Overall, 137 of 151 lesions subjected to biopsy (90.7%) were melanocytic: 86 DN (57.0%), 40 nevi without atypia (26.5%), and 11 melanomas (7.3%). Of 78 DN, 68 (87.2%) were removed with clear histopathologic margins (8 DN were excluded because of inadequate processing). There was no clinical evidence of recurrence at any of the biopsy sites that were simply observed (i.e., not re-excised) over a median of 16.9 months.
Limitations: There were few biopsies performed on the face.
Conclusions: The complete histopathologic removal of nearly 9 of 10 DN using a peripheral margin of 2 mm of normal skin and a depth at the dermis and subcutaneous fat junction has the potential to decrease second procedures at DN biopsy sites, thereby decreasing patient morbidity and saving health care dollars.
(Copyright © 2017 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.)