Dermoscopy of a plantar combined blue nevus: a simulator of melanoma

Abstract

Dermoscopy allows early detection of melanoma also on acral volar skin. The majority of melanocytic nevi on palms and soles may show three major dermoscopic patterns: the parallel-furrow pattern, the lattice-like pattern, and the fibrillar pattern. Melanomas at these sites are characterized by the parallel ridge pattern. We present the case of a 59-year-old woman who had an oval papule of bluish color, measuring 0.6 x 0.9 cm, localized on her left sole, that had been present, unchanged, for more than 10 years. Dermoscopy showed a parallel ridge pattern. The histopathological examination revealed a combined blue nevus. We present this case to underline that on acral volar skin also intradermal nevi, such as combined blue nevi, may dermoscopically exhibit a parallel ridge pattern, simulating melanoma.