Human papillomavirus DNA and liquid-based cervical cytology cotesting in screening and follow-up patient groups

To compare the use of human papillomavirus (HPV) DNA and cervical cytology cotesting in screening and follow-up of patients with previous cervical abnormalities and to assess the significance of a positive HPV DNA test result in re-screening of cytologically normal cases.

Cellular samples collected in liquid-based fixative were used for both cervical cytology and HPV DNA testing. The cervical cytology slides were manually screened by cytotechnologists followed by rapid re-screening by pathologists. The HPV DNA tests were performed using hybrid capture test kits. Statistical analyses of cervical cytology results and HPV DNA tests for high- and low-risk HPV from both patient groups were carried out.

The prevalence of HPV DNA-positive cases was higher in younger patients. There was a poor correlation between cervical cytology results and HPV DNA tests for the screening group (kappa = 0.23), but a fair to good correlation was obtained for the follow-up group (kappa = 0.51). The false negative fraction of cytology negative/HPV DNA positive cases (0.1317), as compared with cytology negative/HPV DNA negative cases (0.0056), was statistically significant (p = 0.000001).

The prevalence of HPV DNA decreased with increasing age in both the screening and follow-up patient groups. Virus clearance was delayed in the follow-up group as compared with the screening group. There was a poor correlation between cervical cytology and HPV DNA tests in the screening group but a fair to good correlation in the follow-up patient group. Cotesting of HPV DNA and cervical cytology increases the sensitivity and decreases the false negative fraction, suggesting that cotesting could be used to increase the interval of screening.