Demographic study of clinically atypical (dysplastic) nevi in patients with melanoma and comparison subjects.

We examined 296 patients with a history of melanoma and 145 controls for the presence of atypical (dysplastic) nevi. We found that 34% of patients with melanoma and 7% of controls had clinically atypical (dysplastic) nevi. Patients and controls with atypical (dysplastic) nevi had more nevi than the subjects without. The number of nevi varies negatively and significantly with age (r = 0.37, P less than 0.001). Ten % of patients and controls had hypopigmented halos around one or more nevi. Both patients and comparison subjects with atypical (dysplastic) nevi tended to have this subtle variant of halo nevi more often than those without (r = 0.17, P less than 0.01). The number of nevi on the irides of melanoma patients was greater than that in the comparison group. The results of this study suggest that patients with a melanoma exhibit more commonly cutaneous and ocular pigmentary lesions than comparison subjects without a melanoma.