Reflectance Confocal Microscopy Features of Nevoid Melanoma: Case Report and Literature Review
TL;DR
This case supports a more continuous rather than dichotomous view of NM confocal morphology and highlights the value of integrating clinical, dermoscopic, and confocal findings for early recognition and appropriate management.
Abstract
Nevoid melanoma (NM) is a rare melanoma variant that often mimics benign compound or intradermal nevi, both clinically and histopathologically. Due to its deceptively benign appearance, diagnosis is frequently delayed, resulting in advanced Breslow thickness at presentation. Although dermoscopy offers limited discriminatory power, reflectance confocal microscopy (RCM) provides near‐histopathologic, in vivo resolution; however, standard RCM algorithms may underperform in recognizing this rare subtype. We report the case of a 41‐year‐old woman with a growing 10‐mm pink nodular lesion on the right scapula. Dermoscopy revealed polymorphous vessels and chrysalis structures, while RCM showed disruption of the epidermal honeycomb pattern, atypical cells within the spinous‐granular layers, disarrangement of the dermo‐epidermal junction architecture, and atypical cell aggregates in the upper dermis. These findings were highly suspicious for malignancy and prompted immediate excision. Histopathology confirmed NM (Breslow thickness 5.7 mm), and ancillary molecular testing revealed an isolated MYB (6q23) deletion alongside a BRAF V600E mutation. Based on the available literature, we discuss two confocal phenotypes of NM, a pagetoid/junctional type and a pure‐nest type with preserved epidermal architecture, but show that our case displayed overlapping features and could not be assigned unequivocally to either pattern. This case supports a more continuous rather than dichotomous view of NM confocal morphology and highlights the value of integrating clinical, dermoscopic, and confocal findings for early recognition and appropriate management.