[Clinical utility of reflectance confocal microscopy for the non-invasive diagnosis of lentigo maligna melanoma].

BACKGROUND

Lentigo maligna melanoma (LMM), a melanoma subtype that arises on sun-damaged facial skin, is difficult to diagnose clinically. Patients and physicians are reluctant to perform unnecessary facial biopsies. Reflectance confocal microscopy (RCM) is a novel technique for non-invasive skin imaging at cellular-level resolution. RCM increases the accuracy of melanoma diagnosis.

AIMS: To describe the diagnostic utility of RCM in cases of clinically and dermatoscopically equivocal pigmented skin lesions suspicious for LMM.

METHODS

This is a retrospective case series derived from the population of patients undergoing periodic skin cancer screening at a tertiary hospital clinic that specializes in skin cancer diagnosis. All patients consented to RCM imaging as an ancillary test prior to the decision on performing a biopsy in the facial lesion.

RESULTS

We report on four patients who presented clinically and dermatoscopically equivocal pigmented skin lesions in the head and neck region, with differential diagnosis of LMM. Furthermore, in two patients, a prior incisional biopsy indicated a benign diagnosis upon histopathological analysis. In all cases, RCM examination showed specific criteria for LMM. The RCM diagnosis of LMM allowed direct referral for excisional surgery in three patients. In another patient, RCM findings guided incisional biopsy-site selection to a focus that revealed histopathology clear-cut criteria for LMM.

CONCLUSIONS

RCM is a very useful adjunct to the non-invasive diagnosis of LMM.