P16 and Ki-67 expression improves the diagnostic accuracy of cervical lesions but not predict persistent high risk human papillomavirus infection with CIN1.

Objective: To determine the association between the expression of p16 and Ki-67 and cervical lesions, and to evaluate the role of p16 and Ki-67 as prognostic markers for persistent high risk human papillomavirus (hr-HPV) infection.

Methods: Totally 1,154 cases of cervical biopsies were enrolled, 331 cases with negative for dysplasia (NEG), 462 with cervical intraepithelial neoplasia 1 (CIN1), 176 with CIN2, 163 with CIN3 and 22 with cervical squamous cell carcinoma (SCC). Furthermore, 283 women with CIN1 were recruited into 12-month follow-up, and HPV specific gene detection by polymerase chain reaction was used to detect hr-HPV of cervical secretions at 6-month-interval for 12-month follow-up period. 40 women were infected with persistent hr-HPV, 182 with transient infection and 61 unfected with hr-HPV. The expression of p16 and Ki-67 were evaluated by immunohistochemical method. The immunostaining results of p16 and Ki-67 were classified into four categories: negative, 1+, 2+ and 3+.

Results: There was significant increase in the expression of p16 (P<0.001) and Ki-67 (P<0.001) from NEG to SCC. The expression of Ki-67 (P<0.001) but not p16 (P=0.254) significantly increased in CIN2, CIN3. Ratio of p16 (P=0.215) and Ki-67 (P=0.495) positivity were not correlated with persistent hr-HPV infection.

Conclusions: P16 and Ki-67 can improve the diagnostic accuracy of cervical lesions but can not predict persistent hr-HPV infection with CIN1.