Objective: Previous findings from cross-sectional studies have shown human papillomavirus (HPV) testing to be more sensitive than cytology testing for primary cervical screening. This systematic review aims to assess whether the increase in baseline detection with HPV testing corresponds to lower rates in subsequent screening rounds.
Methods: We searched Medline, EMBASE, and the Cochrane Library for randomized controlled trials (published from 2005 to 2010) comparing HPV-based and cytology-based cervical screening. Primary outcomes of interest were relative rates of higher grade cervical intraepithelial neoplasia and invasive cervical cancer. Secondary outcomes included test performance characteristics and colposcopy referral rates. Results were pooled where possible using a random effects model.
Results: Seven randomized trials were identified. Across studies, HPV testing was more accurate than conventional cytology and detected significantly more CIN3+ in the first screening round (Mantel-Haenszel [M-H] risk ratio 1.67; 95% CI 1.27 to 2.19) and significantly less in the second screening round (M-H RR 0.49; 95% CI 0.37 to 0.66). There were no differences in pooled rates of CIN2+ (M-H RR 1.19; 95% CI 0.94 to 1.50) and CIN3+ (M-H RR 1.09; 95% CI 0.84 to 1.42), but there was a higher pooled rate of CIN2 (M-H RR 1.37; 95% CI 1.12 to 1.68) over two screening rounds. A trend towards lower rates of invasive cervical cancer was observed.
Conclusion: Organized screening programs in higher resource settings should consider adopting HPV testing as the primary screening test for women 30 or 35 years of age and older. Further research is needed to determine optimal screening strategies for younger women.