P16/Ki67 dual stain triage versus cytology in primary human papillomavirus-based cervical cancer screening with limited genotyping.

Abstract

The introduction of primary human papillomavirus (HPV) cervical cancer screening requires the implementation of an appropriate triage strategy that will be effective in detecting high-grade cervical disease without losing diagnostic specificity. From the 30.066 screening tests results, a total of 1086 with available high-risk human papillomavirus (HRHPV) with limited genotyping, cytology, and p16/Ki67 dual-stain were selected. Two triage strategies for primary HPV screening were analyzed retrospectively based on the study group. Performance characteristics for p16/Ki67 and cytology triage in the detection of cervical intraepithelial neoplasia grade 2 or worse (CIN2+) and grade 3 or worse (CIN3+) were calculated, detected in colposcopic biopsy. In HPV16/18-positive cases, primary HPV with p16/Ki67 triage was significantly more specific than cytology (53.1%/16.8% for CIN2+; p < 0.0001; 45.9%/17.0% for CIN3+; p < 0.0001), with yielded sensitivity (95.7%/84.8% for CIN2+; p = 0.0955; 100.0%/87.5% for CIN3+; p = 0.0832). In other HRHPV-positive cases (N16/N18), p16/Ki67 triage was also significantly higher specific (51.3%/15.3% for CIN2+; p < 0.0001; 44.5%/16.5% for CIN3+; p < 0.0001), with sensitivity (92.3%/74.4% for CIN2+; p = 0.0522; 90.9%/81.8% for CIN3+; p = 0.5637). Diagnostic predictive values were significantly higher for p16/Ki67 triage with the highest PPV in HPV16/18-positive cases for CIN2+ (45.4%; 95% confidence interval [CI]: 35.2-55.8; p < 0.0001) and very high NPV in all HPV-positive cases regardless of detected genotype (96.3%-100.0%). The risk (1-NPV) for CIN3+ in HRHPV16/18-positive/p16/Ki67-negative women was 0.0%. Superior diagnostic performance compared to cytology for detecting cervical cancer precursors indicates that p16/Ki67 dual-immunostain may be a highly effective tool of triage in primary HPV screening with limited HPV 16/18 genotyping in secondary cervical cancer prevention.