Vulva, vulvar intraepithelial neoplasia

Early (non‐invasive) vulvar cancer, or vulvar intraepithelial neoplasia (VIN) can be HPV‐associated or differentiated type. Although basaloid morphology is usually associated with HPV, this case is an example of a VIN lesion arising in an older patient without evidence of HPV infection (see attached image showing negative p16 immunohistochemical stain.) The diagnosis is based on the degree of atypia seen in the basal layer. The p53 and MIB‐1 stains highlight the cells of interest in this case, but are not necessary for routine diagnosis.