Videodermoscopic pattern analysis of acral melanocytic nevi.

Three major and three minor types of acral melanocytic lesions have been described: parallel furrow, lattice-like, fibrillar, reticular, homogeneous and globular. To examine the dermoscopic patterns of acral melanocytic lesions and to investigate the association of these patterns with clinical features. This study included 419 acral melanocytic lesions of 295 patients. Dermoscopic images were stored in a standardized digital system and assessed. The incidence rates of the patterns were as follows: parallel furrow (62.5%), reticular (12.2%), globular (7.6%), fibrillar (5.0%), lattice-like (4.3%), homogeneous (3.8%), non-typical (3.8%), globulostreak-like (0.5%) and parallel ridge (0.2%). There was a significant association between pattern and diameter; nevi showing globular pattern were significantly smaller than those showing lattice-like pattern. There was a significant correlation between pattern and localization. The fibrillar pattern was observed more commonly on the feet, and the lattice-like pattern was seen almost entirely on the hands. Homogeneous and globular patterns were proportionately more common on the feet than on the hands. A significant association was found between patterns and colors. Compared with the lattice-like pattern, parallel furrow, fibrillar and homogeneous patterns were lighter in color; the globular pattern was darker than the homogeneous pattern. There was no significant correlations between pattern and clinical presentation. In conclusion, unlike all other studies, in the present study, the two most common patterns following the parallel furrow pattern were reticular and globular, which are minor patterns. Besides the differences in pattern distribution and inherent variability in individual assessment, the age of the study group and location of nevi influence the pattern, possibly in association with race.