Handheld reflectance confocal microscopy: Personalized and accurate presurgical delineation of lentigo maligna (melanoma)

Background: The surgical treatment of lentigo maligna melanoma is associated with high rates of local recurrence. Handheld reflectance confocal microscopy (HH-RCM) allows for in vivo presurgical detection of subclinical lentigo maligna (melanoma) (LM/LMM). Methods: A single-center retrospective study from December 2015 to July 2017. Frequency and extent of negative surgical margins, and the diagnostic accuracy of presurgical mapping by HH-RCM was determined. Results: Twenty-six consecutive patients with LM/LMM were included. In 45.8%, HH-RCM detected subclinical LM with a sensitivity of 0.90 and specificity of 0.86. The management was changed in two (7.7%) patients. Of the 24 remaining lesions, 95.8% were excised with negative margins with a mean histological margin of 3.1 and 5.3 mm for LM and LMM, respectively. At a mean follow-up of 36.7 months, there was one (4.8%) confirmed recurrence. Conclusions: Our method of presurgical delineation by HH-RCM appears to provide a reliable method for the surgical treatment of LM/LMM with a limited rate of overtreatment.