Optimizing management of actinic keratosis concerning for underlying carcinoma in anatomically sensitive locations: Application of complete circumferential peripheral and deep margin assessment

Abstract

To the Editor: We define ‘‘special actinic keratoses (AKs)’’ by 2 criteria: (1) location on anatomically sensitive sites that are cosmetically important ( face) or tight skin (scalp, hands, feet, or lower legs) and (2) partial biopsy showing a complex AK extending to the base of the biopsy specimenwithout exclusion of carcinoma. Destructive treatments do not allow evaluation of underlying carcinoma. For AKs in esthetically sensitive locations, a vertically sectioned deeper biopsy/excision may generate a defect that requires a complex repair to avoid distortion of a free margin. We propose that for this special group of AKs, the concept of complete circumferential peripheral and deep margin assessment (CCPDMA) may be applied with an intention to remove the lesion completely yet conservatively. We analyzed how Mohs surgeons in our department manage ‘‘special AKs’’ and whether CCPDMA was utilized. We performed a retrospective chart review, approved by the institutional review board of the University of Wisconsin, of patients referred to Mohs clinic at our institution from January 1, 2012, to January 1, 2021, for AKs with a comment that carcinoma could not be excluded. Patients were identified via an electronic health link (Epic) search and review of relevant pathology reports. The pathology slides were read by any of the 3 boardcertified dermatopathologists within our department (DDB). All patients were managed by any of the 3 fellowship-trained Mohs surgeons within our department (YGX). There were no exclusion criteria. Our search revealed 29 patients, with a total of 30 sites, that met the above criteria. Clinical details and treatment course are outlined in Table I. Fourteen of 30 cases were directly treated with CCPDMA with intraoperative en face frozen section analysis without undergoing a repeat deeper biopsy. Eight of these cases revealed squamous cell carcinoma (SCC) or SCC in situ (SCCis), and therefore, Mohs surgery was appropriately billed. Of the 8 cases with positive