In vulvar intraepithelial neoplasia (VIN) lesions, p16 is considered overexpressed when there is block-like staining, i.e., a strong nuclear and cytoplasmic staining of all lesional cells from the basal layer upwards through at least one-third of the epithelial thickness [43,44]. This evidence concerns the gene CDKN2A and vulvar intraepithelial neoplasia.