Lentigo maligna

**Definition:** An atypical proliferation of atypical melanocytes in the dermal-epidermal junction, without infiltration of the papillary or reticular dermis. The melanocytic proliferation is associated with actinic damage and epidermal atrophy. It usually occurs in the sun-exposed skin of elderly people. It is a form of melanoma in situ and in approximately 5% of cases it progresses to lentigo maligna melanoma.