Acral melanoma with hyperkeratosis mimicking a pigmented wart

Acral lentiginous melanoma (ALM) of the sole sometimes has a hyperkeratotic appearance and mimics a pigmented wart. We report a case of an 81-year-old woman with an ALM on the left sole with hyperkeratosis. Due to its presentation it was difficult to make a correct diagnosis at the beginning. Finally we noticed several small, pigmented macules around the wart-like lesion with the parallel ridge pattern on dermoscopy, strongly suggesting acral melanoma. When a hyperkeratotic pigmented lesion on the sole is encountered, one should rule out melanoma by careful examination of the periphery of the lesion. Dermoscopy is a helpful adjunct for the diagnosis of an unusual case like this.