Histologic correlations with the clinical diagnosis of dysplastic nevus.

In melanoma kindreds the presence of dysplastic nevi correlates with greatly increased melanoma risk. The relative importance of sporadic, nonfamilial dysplastic nevi as a risk factor for melanoma is less certain. Although the clinical features of dysplastic nevi have been well described, the histologic basis for the diagnosis is not as firmly established. This study examines the degree of correspondence between the clinical and histopathologic diagnosis of dysplastic nevus. Histologic review of nevi with clinical features of dysplasia from 1,000 individuals demonstrated classic histologic features of dysplasia (as previously demonstrated in melanoma kindreds) in 54.7%. In 20.4% of patients, nevi displayed less convincing or only partially developed features of dysplasia. The remaining patients (24.9%) had nevi of other types. Correspondence between the clinical and histologic diagnosis of dysplasia was best for lesions from the trunk and in individuals beyond the age of 20 years. This study supports the validity of the dysplastic nevus as a clinical and pathologic entity.