A comparative analysis of lichen sclerosus of the vulva and lichen sclerosus that evolves to vulvar squamous cell carcinoma.

Abstract

The aim of this study was to determine whether the premalignant change in lichen sclerosus (LS) could be identified with immunohistochemical analyses. Eight cases of histologically diagnosed vulvar LS, which showed, after a period of 10 months-9 years, an evolution to carcinoma of the vulva that was histologically documented, were compared with 8 cases of vulvar LS, for which follow-up information was available for at least 9 years. The proliferative index and the expression of tumor suppressors p16 and p53 were analyzed. The difference of MIB1 labeling index of evolving or unchanged LS cases was significant (P = .005). The difference in the p53 of evolving or unchanged LS cases shows a trend towards association (P = .08). Both LS cases (evolving or unchanged) did not show p16 positive staining. The evaluation of MIB1 and p53 may identify those vulvar LS cases with a high likelihood of evolving into squamous cell carcinoma, which would need careful periodic checks or adjunctive biopsies. The study must be confirmed by a larger number of cases to substantiate this observation.