Mohs micrographic surgery (MMS) with MART-1 immunostaining for atypical intraepidermal melanocytic proliferation (AIMP)

Publication date: Available online 10 July 2018

Source: Journal of the American Academy of Dermatology

Author(s): Jeremy R. Etzkorn, Olivia S. Jew, Thuzar M. Shin, Joseph F. Sobanko, Donald E. Neal, Christopher J. Miller

Abstract

Background

The efficacy of Mohs micrographic surgery (MMS) for atypical intraepidermal melanocytic proliferation (AIMP) is unknown.

Objective

To ascertain the frequency of diagnostic change to melanoma (upstaging) and the frequency of local recurrence after MMS for AIMP. A secondary outcome was the frequency of subclinical spread (defined as the requirement for greater than one stage of MMS to achieve tumor-free margins).

Methods

Retrospective, cross-sectional study of 223 AIMP (with 92.4% located on the head, neck, hand, foot, or pretibial leg) treated with MMS with MART-1 immunostaining.

Results

Upstaging to unequivocal MIS or invasive melanoma was identified in 18.8% (42/223) of all AIMP. The local recurrence rate was 0% (0/223) with a mean follow-up time of 2.7 years (998 days). Subclinical spread was present in 23.8% (53/223) of AIMP.

Limitations

Single site, retrospective design, observational study, lack of objective criteria to diagnose AIMP

Conclusion

MMS with MART-1 immunostaining achieves excellent local control of specialty-site AIMP and permits definitive removal of subclinical spread prior to reconstruction. The central debulking excision should be evaluated with formalin-fixed paraffin-embedded sections, since a significant percentage of AIMP are reclassified as MIS or invasive melanoma.