HPV triage for low grade (L-SIL) cytology is appropriate for women over 35 in mass cervical cancer screening using liquid based cytology

In the experimental arm of a randomised trial, women were tested both for liquid-based cytology and human papillomavirus (HPV) DNA and referred for colposcopy if cytology was ASCUS (atypical cells of undetermined significance) or more severe. We considered those with ASCUS (757) or LSIL (low-grade squamous intraepithelial lesions) (485) and a valid HPV test who received colposcopy. We computed sensitivity, specificity and ROC curves with different values of relative light units (RLU, that are related to viral load) as cut off, using cervical intraepithelial neoplasia grade 2 or more severe (CIN2+) at blind histology review as the endpoint. The area under the receiver operating characteristic (ROC) curve was significantly less among women aged 25–34 years than in those older, both considering ASCUS/AGUS (atypical glandular cells of undetermined significance) (p = 0.0355) and LSIL (p = 0.0009). At age 35–60 the curves for ASCUS and LSIL were similar, while at age 25–34 the area under the curve for LSIL was significantly less than for ASCUS (p = 0.0084). With LSIL cytology, specificity of Hybrid Capture 2 with 2 RLU cut-off was 35.0% (95%CI 28.4–42.1) at age 25–34 and 64.5% (95%CI 58.3–70.3) at age 35–60. In conclusion, triaging by HPV testing performed better in women aged over 35 years than those younger. For older women, HPV triaging should also be considered for managing those with LSIL cytology.