Dermoscopic features of acral melanocytic nevi in a case series from Mexico

BACKGROUND: Pigmented lesions on acral sites are common; clinical differentiation of nevi and early melanoma can be challenging. In these cases, dermoscopy can provide a more accurate diagnosis. Most dermoscopic patterns on acral skin have been described in Asian and European populations, while there are few studies in Latin American populations. OBJECTIVES: To determine the frequency of pigmented lesions in volar skin and their dermoscopic patterns in a Mexican population. Methods: An observational, descriptive, cross-sectional study was performed in Hispanic patients with the presence of at least one pigmented lesion on acral skin. Clinical and dermoscopic images were obtained. These were subsequently evaluated independently by two dermatologists trained and experienced in dermoscopy. RESULTS: A total of 582 pigmented lesions on volar skin were diagnosed in 321 patients. Overall, prevalence of acral pigmented lesions on volar skin was 6.8%. For both observers, parallel furrows were the most frequent pattern described, but for observer 2, a lattice-like pattern was prevalent on the toes and a homogeneous pattern on the sides of the feet. There was lower inter-observer agreement, with a kappa index of 0.144. STUDY LIMITATIONS: The lesions were not biopsied, so clinical-histological correlation could not be performed. The study did not correlate dermoscopic patterns with age. CONCLUSIONS. As previously reported by other authors, parallel furrows were the most frequently found dermoscopic pattern on palmoplantar skin.