p16/Ki-67 Dual Staining Is a Reliable Biomarker for Risk Stratification for Patients With Borderline/Mild Cytology in Cervical Cancer Screening

Background/Aim: To evaluate p16/Ki-67 dual staining performance for detection of cervical intraepithelial neoplasia grade 2 or worse (CIN2+) in the management of women with minor cervical abnormalities. Patients and Methods: All 759 enrolled patients were tested for cytology, high-risk human papillomavirus (HR-HPV) and dual p16/Ki67 staining. Results: Positivity rates for HR-HPV and dual staining increased as dysplasia was worsened from non-CIN (37.6% and 0%) to CIN1 (62.5% and 1.6%) and CIN2+ (98.7% and 97.3%), respectively. HPV18 and HPV16 exhibited the highest odds ratios (53.16 and 11.31) in the CIN2+ group. Both p16/Ki-67 dual staining and HR-HPV presented similar sensitivities (97.3% and 98.7%, respectively) for CIN2+ detection. Dual staining specificity, however, was 99.3%, significantly higher compared to HRHPV testing (52.2%). The utility of dual staining was evaluated in different screening strategies and appeared to reduce the number of colposcopies required for the detection of CIN2+ cases. Conclusion: p16/Ki-67 dual-staining cytology is a surrogate triage biomarker in cytology-based screening programs, with high performance for efficient risk stratification of women with mild cervical abnormalities.