Clinicopathologic analysis of 370 cases of vulvar intraepithelial neoplasia

OBJECTIVE: To investigate epidemiologic, clinical and pathologic aspects of various grades of vulvar intraepithelial neoplasia (VIN). STUDY DESIGN: A retrospective, multicenter study of 370 cases of vulvar intraepithelial neoplasia (VIN) was performed by the Italian Study Group on Vulvar Disease. RESULTS: Of the 370 cases, 148 were VIN 1 (40.0%), 53 were VIN 2 (14.3%), and 169 were VIN 3 (45.7%). The mean age of the patients was 52.6 years. During the study period an increase in the rate of human papillomavirus-associated VIN was observed. In addition, while VIN 1 and 2 were associated mostly with squamous cell hyperplasia, VIN 3 was almost equally associated with lichen sclerosus and squamous cell hyperplasia; the difference was statistically significant. Intraepithelial or invasive squamous neoplasia of the lower genital tract was associated in 22% of the cases (82/370). CONCLUSION: The results of the investigation, although not allowing firm conclusions due to the retrospective and multicentered nature of the study, demonstrate the extreme heterogeneity of VIN lesions.