Comparing preoperative mapping with reflectance confocal microscopy to surgical markings in lentigo maligna excision of the face: a pilot study

Lipi Shukla,Frank Bruscino-Raiola,Raquel Ruiz,John Kelly,Ramin Shayan,Alan Pham,Catriona Mclean,Victoria Mar,Louise Photiou

doi:10.34239/ajops.v3n2.165

Abstract

Background: Lentigo maligna (LM) characteristically has an ill-defined margin and may require multiple excisions to achieve complete excision with 5mm margins. In vivo reflectance confocal microscopy (RCM) is a non-invasive tool recognised as useful in the management of LM. The authors aimed to determine whether the use of RCM prior to surgical excision reliably increased the rate of complete excision when compared with standard surgical excision. Methods: This prospective pilot study included patients with biopsy-proven LM of head and neck region who sought consultation for surgical management from May 2017 to May 2019 at the Victorian Melanoma Service, Melbourne. Patients were randomised to two groups based on the availability of RCM — Group 1, RCM-guided surgical excision, and Group 2, standard surgical excision. Outcomes were measured based on clinical markings and histopathological margins achieved and reported as RCM or surgical margin excess or deficit. Ethics approval for the study was obtained from the Research Governance Unit of The Alfred Hospital, Melbourne. Results: Results demonstrated that RCM marking of lesion margins was in excess in 69 percent of cases, in deficit in 22 per cent and accurate in nine per cent after histopathological analysis of the specimens. In comparison, lesions that were surgically marked were removed with margins in excess in 43 per cent of cases, in deficit in 11 per cent and accurate in 46 per cent. Conclusion: This pilot study demonstrates that RCM did not increase the accuracy of LM surgical excision in comparison with standard surgically marked excisions.

Highlights

Lentigo maligna (LM) is a form of melanoma in situ that predominantly occurs on the exposed and sundamaged skin of older people
LM can be light brown, darker brown, black or skin-coloured and can have small clusters of melanoma cells located in a scattered fashion around the main lesion, making it notoriously difficult to define the edges of the lesion with the naked eye
Recurrences of LM often occur at the margins of previously treated areas, either as a result of inadequate surgical margins or by ‘field cancerisation effect’ in secondary procedures, as supported by Agarwal-Antal and colleagues’ findings, which demonstrated that 5 mm margins cleared less than 50 per cent of the LM lesion—92 cases excised with these margins demonstrated a clearance rate of 42 per cent at the first procedure and 69 per cent at the second procedure.[3]

Summary

Introduction

Lentigo maligna (LM) is a form of melanoma in situ that predominantly occurs on the exposed and sundamaged skin of older people. It is associated with a higher incidence of local recurrence than other common melanoma subtypes.[1] LM can be light brown, darker brown, black or skin-coloured and can have small clusters of melanoma cells located in a scattered fashion around the main lesion, making it notoriously difficult to define the edges of the lesion with the naked eye. The authors aimed to determine whether the use of RCM prior to surgical excision reliably increased the rate of complete excision when compared with standard surgical excision

Methods

Results

Discussion

Conclusion