ObjectiveTo determine trends in the clinicopathology of vulvar squamous cell carcinoma over the past 2 decades, with particular reference to the possible effects of the increasing incidence of vulvar intraepithelial neoplasia (VIN) during this time.MethodsTwo cohorts of 56 and 57 women with squamous cell carcinoma of the vulva and separated by at least 2 decades were reviewed retrospectively. Pathologic specimens were analyzed concurrently.ResultsIn the 1965–1974 cohort, only one of 56 patients was younger than 50 years of age at the time of presentation, whereas in the 1990–1994 cohort, 12 of 57 (21%) were younger than 50 years of age (P= .001). Ten of 13 women younger than 50 years of age, compared with 13 of 100 of women 50 years of age or older, had warty or basaloid VIN associated with their invasive carcinoma (P< .001). Cigarette smoking and multiple lower genital tract neoplasia were both significantly more common in women younger than 50 years of age (P< .001).ConclusionOver the past 2 decades, a subset of women younger than 50 years of age with squamous cell carcinoma of the vulva has emerged. Most of these carcinomas appear to arise in a field of warty or basaloid VIN. This suggests that the increasing incidence of VIN seen in young women during the past 2 decades is being reflected now in VIN-associated squamous cell carcinoma of the vulva in younger women.