Melanoma in situ on facial skin damaged by sunlight

Solar lentigines ("liver spots") commonly occur on sun-damaged skin in the elderly population. Although they are benign, it is difficult in practice to distinguish solar letigines and junctional nevi from melanoma in situ. We report a patient who developed melanoma on the same site as a previously diagnosed solar lentigo. We also review the histopathological criteria for differentiating these benign lesions from potentially malignant ones.