Atypical dermoscopic presentation of an acral congenital melanocytic nevus in an adult: parallel ridge pattern and its histologic correlation.

Acral melanoma is the most frequent subtype in the Asian and Mexican mestizo populations. Dermoscopy is a noninvasive diagnostic technique that helps the differential diagnosis of pigmented skin lesions on acral volar skin. We, herein, present a case of acral congenital melanocytic nevus with a parallel ridge dermoscopic pattern. Since the parallel ridge pattern in a melanocytic lesion of the acral skin is classically ascribed to melanoma, the present case can be definitely labeled as "atypical" and worth of being elucidated in its histopathological correlates.