The melanocytic nevus described by Clark et al. What is its nature? What should it be named? An answer from history and from logic.

The article by Shapiro et al., which summarizes a survey of respondents on the words or phrases they use to identify the melanocytic nevus described by Clark et al. in 1978, shows that over 70% of The American Society of Dermatopathology (ASDP) members and nearly 85% of The American Academy of Dermatology (AAD) members preferred one of the following phrases: ‘‘dysplastic nevus’’, ‘‘nevus with architectural disorder’’, ‘‘atypical nevus’’, or ‘‘atypical melanocytic hyperplasia’’. Only about 11% of the ASDPmembers and less than 5% of the AAD members identified the nevus as either a ‘‘Clark’s nevus’’ or a ‘‘compound nevus’’, thereby avoiding the designations ‘‘dysplastic’’, ‘‘architectural disorder’’, and ‘‘atypical’’. This article revealed one important fact about the nature of the melanocytic nevus that has for over 26 years eluded and confounded dermatopathologists, pathologists, and dermatologists alike. The fact is that the disparate, inconsistent nomenclature applied to this particular type of melanocytic nevus reflects a conceptual conundrum that exists in the minds of susceptible histopathologists. This nomenclature results in producing confusion and uncertainty and implies that melanoma cannot be excluded in these lesions vis-à-vis the pairing of the terms ‘‘atypical’’, ‘‘dysplastic’’, or ‘‘disordered’’ (implying that one cannot exclude malignancy) with ‘‘melanocytic nevus’’ (a phrase of certainty that refers to a hamartoma or benign neoplasm). The actual melanocytic nevus in question is, however, either a hamartoma or a benign neoplasm that never killed anyone and never will. Its diagnosis should, therefore, be clean, clear, and unequivocal. What is the origin of this uncertainty? Why have 26 years, two consensus conferences (resulting in no consensus), and tens of millions of dollars of National Institutes of Health’s grant money failed to produce a rational, uniform approach to the diagnosis of this type of melanocytic nevus? In my opinion, there are several reasons for this failure, chief among which are: