Parallel ridge pattern seen on dermoscopic examination of melanoma of the palms and soles

The parallel ridge pattern represents band-like pigmentation on the ridges of the skin markings. In this melanoma in situ (A), the pattern covers almost all the lesion. In an early invasive melanoma of the sole (B), the parallel ridge pattern is detected only in the lower portion of the lesion (circle), and irregular, diffuse pigmentation is observed in the upper portion.