The so-called dysplastic nevus is not dysplastic at all

In a recent two-part essay entitled “The dysplastic nevus: from historical perspective to management in the modern era” published in the Journal of American Academy of Dermatology, Duffy and Grossman concluded, following comprehensive literature review, historically, histologically, clinically and molecularly, that the so-called dysplastic nevus is a type of melanocytic nevus and should be managed like other types of melanocytic nevi [1,2]. This reinforces the notion set forth by the late Bernie Ackerman, who asserted more than two decades ago that the so-called dysplastic nevus is the commonest melanocytic nevus in man [3]. Duffy and Grossman acknowledged that the term dysplastic nevus is inappropriate, however, they did not advocate change of the term in these words: “the term ‘dysplastic nevus,’ despite its problems, should not be abandoned—it has become entrenched in our dermatologic language and practice.” [1] We believe the authors underestimated the ramification of continuing the use of an inappropriate term. Historically, the introduction of the term dysplastic nevus was based on an assumption, which has been found to be incorrect. Clark and coworkers believed in the multistep carcinogenesis theory and thought that the lesion under discussion represented an intermediate step between nevus and melanoma. In an article by Clark and coworkers, they expressed this view in these words: “[dysplastic nevi] fit nicely into the schema of progression from hyperplasia to dysplasia to neoplasia that is accepted in many epithelial tumor systems, both experimental and human” [4]. As one examines the literature, there is really no evidence in support of the multistep carcinogenesis theory and there is no intermediate entity between nevus and melanoma [5]. Secondly, although the word “dysplasia” has never been lucidly defined in pathology, whenever the word dysplasia is used in tumor pathology, it generally refers to intraepithelial neoplasia with cytomorphologic features of malignancy, namely, carcinoma in situ lesions, by surgical pathologists. If one looks for an equivalent lesion to the so-called dysplastic (carcinoma in situ) lesions of epithelial tissue in melanocytic neoplasia, melanoma in situ would be the one, not the socalled dysplastic nevus. We have come to know the lesion under discussion is as a variant of melanocytic nevus and the commonest nevus in humans. In other words, it is totally benign and not dysplastic at all, namely, neither an intermediate step between nevus and melanoma nor a carcinoma in situ equivalent. There is no need to excise it surgically unless other than for cosmetic reasons or suspicion of melanoma. However, such a benign lesion has certainly been overtreated since 1980, when the term dysplastic nevus was first introduced [4], due to the continued wrong belief that it represented an intermediate step between nevus and melanoma or a carcinoma in situ equivalent. A survey by Tripp et al found that 86% The so-called dysplastic nevus is not dysplastic at all