Five-year risk of CIN3 after short-term HPV-DNA negativity in cytology-negative women: a population-based cohort study.

Abstract

To assess the 5-year risk of high-grade lesions in women with a transient high-risk HPV infection. Population-based cohort study. HPV primary testing within population-based organised cervical cancer screening programmes. Italian women enrolled in seven pilot projects and attending the second round. On the basis of the cytology triage performed on HPV-positive women, immediate colposcopy or HPV repeat at 12 months was recommended. Data were collected at the subsequent round 3-4 years after HPV infection clearance. Rates of HPV infection, CIN2+ and CIN3+ detection at subsequent round after HPV clearance, and relative risks (RR) in comparison with HPV-negative women (with 95% confidence interval). Data on 1230 women (1027 aged 25-64 years and 203 aged 35-64 years) have been analysed. Overall compliance with repeat HPV testing was 84%. In comparison with HPV-negative women, those with a transient HPV infection had higher proportions of HPV positivity (15% versus 3.7%) and of CIN2+ lesions (0.87% versus 0.23%) in round two; most of these (7/10) were CIN2; no cancers were detected, and CIN3 occurred in 3/1230 (0.24%). HPV-based protocols for cervical cancer screening allow long intervals for HPV-negative women; it is important to monitor the clinical outcome in the women with transient high-risk HPV infection. CIN3 detection is similar to that observed in routine European cytology-based screening programmes (CIN3+: 2.7‰); 5-year intervals may provide reasonable protection but longer intervals are not recommended. A screening interval of 5 years (but no longer) appears safe in women with transient HPV detection.