Reflectance confocal microscopy for the diagnosis of vulvar melanoma and melanosis: preliminary results

Background: In the early stages, vulvar melanoma can mimic vulvar melanosis and therefore the diagnosis is often late and carries a poor prognosis. In vivo reflectance-mode confocal microscopy (RCM) is an emerging technique that allows noninvasive high-resolution imaging of the skin and mucosa, but it has not been employed in the study of genital pigmentation. Objective: To analyze the characteristics of vulvar melanosis and vulvar melanoma using RCM to define the confocal aspects that allow a correct differential diagnosis. Methods and Materials: Features of eight melanoses and two melanomas of the vulva were analyzed using RCM. RCM diagnosis was then compared with clinical and histologic diagnosis. Results Two major characteristics are associated with vulvar melanosis: papillae rimmed by bright monomorphous cells and possible presence of a few dendritic bright cells in the basal layer of the epithelium. Two major features of vulvar melanoma have been identified: atypical cells in the epithelium and loss of normal architecture of chorion papillae. Conclusions: Reflectance Confocal Microscopy can play a role in noninvasive differentiation between vulvar melanoma and vulvar melanosis, but further broader studies are needed to validate our observations.