Prediction of high-grade cervical intraepithelial neoplasia in cytologically normal women by human papillomavirus testing

Human papillomavirus (HPV) testing has been suggested for primary screening of cervical cancer. Prediction of future high-grade cervical lesions is cr ucial for effectiveness and cost. We performed a case control study in a re trospective cohort of women with at least two cervical smears, all but the last one being negative, from the organized cervical screening programme in Florence, Italy. We searched for high-risk HPV in all previous, archival, smears from cases (new histologically confirmed cervical intraepithelial ne oplasia (CIN) grade It or worse) and in one previous smear from each contro l (last smear cytologically normal, matched by age and interval (latency) f rom last smear). We applied polymerase chain reaction (PGR), and the b-glob in gene was used as a DNA preservation marker. High-risk HPV was identified in 71/92 (77.17%) previous smears from 79 cases and 17/332 controls (5.12% ). The adds ratio (OR) was 63.76 (95% CI 30.57-132.96). Among cases the pro portion of HPV-positive smears declined slightly with increasing latency. A mong cases, HPV was found in 81.24% (95% Cl 69.93-88.96%) of smears with la tency < 4 years and in 67.80% (95% CI 47.72-82.93%) of those taken at longe r intervals, up to 6 years. These findings suggest that testing far high-ri sk HPV allows predicting 80% of CINII/III 3 years before the cytological di agnosis and two thirds 6 years before. They also suggest that testing women negative for high-risk HPV at longer interval and strictly following-up wo men who are HPV positive could be an effective strategy for cervical cancer screening. (C) 2000 Cancer Research Campaign http://www.bjcancer.com.