Histologic criteria for lichen sclerosus of the vulva.

Although lichen sclerosus was first described almost a century ago, a grading system was not devised, and the minimal histologic criteria required for diagnosis were not defined. The present study was based on the sequential sectioning of nine vulvectomy specimens removed for invasive carcinoma. Both epidermal and dermal changes were noted, but only the dermal ones were unique to the disease. Early changes included subtle densification of the basement membrane as well as hyalinization of the papillary dermis and superficial capillaries. Based on these findings, a grading system was developed.