The dysplastic nevus concept

"Dysplastic" nevi (DN), also known as Clark's nevi, are lesions that have characteristic clinical and histologic features that may be a marker for increased melanoma risk in some individuals. The magnitude of the risk of melanoma in patients with DN is dependent on clinical factors, including the number of nevi, and whether there is a personal or family history of melanoma. It has been almost 3 decades since the concept was first well delineated by Clark et al. Nevertheless, the topic remains controversial. Clinicians need to understand the implication of the diagnosis of DN to optimize clinical management of patients. Furthermore, grading DN is difficult to quantify and can lead to confusion. In this review, we attempt to clarify the confusion that surrounds this topic.