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.

CONCLUSION

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