Histologic characteristics of vulvar nevocellular nevi

Reports in the literature stress the premalignant potential of vulvar melanocytic lesions and the unusual histologic features associated with some vulvar nevi in premenopausal women. We examined biopsies of 85 pigmented vulvar lesions taken from women 13 to 73 years of age. There were 59 nevocellular nevi, 16 lentigines, 4 melanomas, and 6 miscellaneous lesions. The nevocellular nevi were compared to a control series of 200 nevi from the torsos of women 20 to 60 years old. Three vulvar nevi were considered to be unusual, but not dysplastic. These histologically unusual nevi occurred in women 20 to 30 years old. The lesions exhibited notable enlargement of junctional melanocytic nests with variability in the size, shape and position of the nests. Similar changes were not observed in the control group. There was a significant association (p less than 0.05) between the occurrence of these unusual lesions and their presentation on the vulva; however, these lesions showed no predilection for any particular site on the vulva. There was no evidence of an increased incidence of vulvar dysplastic nevi when compared with the control series.