Mohs moat: Peripheral cutaneous margin clearance in a collaborative approach for aggressive and deeply invasive basal cell carcinoma

Anticipated Versus Unanticipated Incomplete Mohs Micrographic Surgery for Keratinocyte Carcinomas: Impact on Treatment Delays and Final Margin Status

BACKGROUND

Mohs micrographic surgery may be discontinued with positive margins as an anticipated strategy for multidisciplinary care or as an unanticipated occurrence. Management of primary tumors has not been compared after anticipated versus unanticipated incomplete Mohs micrographic surgery (iMMS).

OBJECTIVE

To compare rates and timing of adjuvant surgery after iMMS and final margin status when iMMS is anticipated versus unanticipated. Secondary outcomes were preoperative and intraoperative clinicopathologic factors associated with iMMS.

METHODS

Cases of iMMS of keratinocyte carcinomas at a tertiary academic center between 2005 and 2022 were classified as anticipated (preoperative assembly of multidisciplinary teams) or unanticipated (ad hoc management of positive margins). Rate, timing, and final margin status of adjuvant surgery was compared between anticipated and unanticipated iMMS cohorts using χ2/Fisher exact test for categorical variables and t-test for continuous variables.

RESULTS

Of 127 iMMS cases, 51.2% (65/127) were anticipated. Anticipated iMMS cases were more likely to undergo additional resection (98.5% vs 72.6%, p < .001), with fewer delays (3.9 vs 13.2 days, p < .001) and higher rates of final margin clearance (84.6% vs 59.7%, p < .001).

CONCLUSION

When iMMS is anticipated as part of multidisciplinary care, patients are more likely to undergo additional resection, with fewer delays to next surgery and higher final margin clearance rates.

The treatment of anogenital extramammary Paget's disease as part of a multidisciplinary approach: The use of Mohs surgery moat method with CK7

Although most cases of extramammary Paget's disease (EMPD) are localized to the intraepidermal, the extensive subclinical extension can lead to high rates of marginal recurrence with wide local excisions and topically destructive treatments. Recurrence rates of EMPD treated with Mohs micrographic surgery (MMS) without immunohistochemical staining are better but variable. Here, we describe our multidisciplinary approach for treating large EMPD tumors of the anogenital region involving critical anatomy using MMS for peripheral margin clearance (moat method) and intraoperative CK7 immunostaining. Our clinical pearls for the management of anogenital EMPD are based on 53 multidisciplinary cases treated at the author's institution between 2014 and 2020.

Mohs Micrographic Surgery at Challenging Anatomical Sites

BACKGROUND

Mohs micrographic surgery (MMS) is often the treatment of choice for skin cancer removal as it maximizes normal tissue sparing and can be paired with a reconstructive approach that optimizes function and cosmesis. Many tumors on the eyelid, nose, ear, and genitals are particularly well suited for MMS but can be challenging for the dermatologic surgeon.

OBJECTIVE

To review the complex anatomy, as well as the authors' approach to executing and interpreting Mohs layers, at each of these anatomical sites.

METHODS

A review of the literature on MMS of the eyelid, nose, ear, and genitals was performed using the PubMed database and relevant search terms.

CONCLUSION

These sites present potential pitfalls for tumor resection and reconstruction, but with the proper technique, the dermatologic surgeon can minimize tumor recurrence and MMS complications. Warning signs for potentially difficult tumor resection can signify when an interdisciplinary approach is warranted.