Immunohistochemical expression of p16(INK4A) in normal uterine cervix, nonneoplastic epithelial lesions, and low-grade squamous intraepithelial lesions.

In this study, the authors analyzed the immunoexpression of p16 in high-risk human papillomavirus DNA-negative normal and nonneoplastic cervical epithelia, in low-grade cervical intraepithelial neoplasia (CIN), high-grade CIN, and squamous cell carcinoma. A retrospective study, in which 58 normal cervical hysterectomy samples, 56 nonneoplastic cervical biopsies, 88 CIN 1, 33 CIN 2, 32 CIN 3, and 47 invasive squamous cell carcinoma biopsies, were evaluated for p16 immunoexpression. Human papillomavirus tests were also performed. p16 immunohistochemistry seems to reveal possible different biological subgroups of lesions among morphologically similar mildly dysplastic cervical epithelia. Distribution patterns of p16 protein might be useful to predict different outcomes in CIN 1.