The IMproving Primary Screening And Colposcopy Triage trial: human papillomavirus, cervical cytology, and histopathologic results from the baseline and 1-year follow-up phase

BACKGROUND: An increase in human papillomavirus test volumes is expected in the near future because human papillomavirus-based screening protocols are expected to become more widely adopted. OBJECTIVE: The IMproving Primary Screening And Colposcopy Triage trial, a prospective, multicenter, US-based cervical cancer screening trial, was conducted to obtain US Food and Drug Administration approvals for the new, high-throughput cobas human papillomavirus (cobas HPV) test for use on the cobas 6800/8800 Systems (cobas HPV) for detecting cervical precancerous and cancerous cells (cervical intraepithelial neoplasia of grade 2 or worse and grade 3 or worse). Here, the baseline demographics, human papillomavirus test results, cervical cytology, and histopathologic results are presented. In addition, the baseline and 1-year risks of cervical intraepithelial neoplasia grade 2 or worse and grade 3 or worse associated with the human papillomavirus results are reported. STUDY DESIGN: In total, 35,263 women aged between 25 and 65 years undergoing routine screening were enrolled; liquid-based cytology and 2 polymerase chain reaction-based tests for high-risk human papillomavirus were performed. Women with abnormal Papanicolaou cytology, women positive for high-risk human papillomavirus by either of the 2 human papillomavirus tests, and a random subset of women negative according to the Papanicolaou cytology and the 2 human papillomavirus tests were referred for a colposcopy and cervical biopsy. Women who did not meet the study endpoint were eligible for the 1-year follow-up study phase. Verification bias-adjusted cervical disease prevalence and risks and 95% confidence intervals were computed. RESULTS: The prevalence of atypical squamous cells of undetermined significance and worse than atypical squamous cells of undetermined significance cytology were 6.5% and 3.2%, respectively. Prevalence of high-risk human papillomavirus, human papillomavirus 16, and human papillomavirus 18 based on the new cobas HPV test were 15.1%, 3.1%, and 1.4%, respectively. Both cytologic abnormalities and human papillomavirus positivity declined with increasing age. Among women who had a colposcopy and biopsy, the prevalence of cervical intraepithelial neoplasia grade 2 or worse and grade 3 or worse were 8.8% and 3.6%, respectively. The baseline and 1-year cumulative risks for cervical intraepithelial neoplasia grade 3 or worse were 13.6% and 16.9%, respectively, among women who tested positive for human papillomavirus 16. Women who tested negative for human papillomavirus had the lowest 1 year cumulative risk for cervical intraepithelial neoplasia grade 3 or worse (0.06%). CONCLUSION: The contemporary, age-specific prevalence of human papillomaviruses (including human papillomavirus 16 and 18), cytologic abnormalities, and cervical intraepithelial neoplasia in a large, US-based cervical cancer screening population provides benchmarks for healthcare policies, screening programs, and for laboratories and clinicians.

Automated summary

The study aimed to obtain FDA approvals for the new cobas HPV test and provided data on cervical precancerous and cancerous cells, as well as the risks associated with cervical intraepithelial neoplasia grade 2 or worse and grade 3 or worse.