High correlation was also found between CIN and p16INK4a/Ki-67 expression in many previous studies evaluating immunohistochemical expression of biomarkers in cervical intraepithelial lesions as an adjunct for a diagnosis of cervical squamous intraepithelial lesion and invasive SCC. This evidence concerns the gene CDKN2A and cervical squamous intraepithelial neoplasia.