In 2012, the US Preventive Services Task Force (USPSTF) and a consensus of 25 organizations endorsed concurrent cytology and human papillomavirus (HPV) testing (“cotesting”) for cervical cancer screening. Past screening and management guidelines were implicitly based on risks defined by Pap-alone, without consideration of HPV test results. To promote management that is consistent with accepted practice, new guidelines incorporating cotesting should aim to achieve equal management of women at equal risk of cervical intraepithelial neoplasia grade 3 and cancer (CIN 3+).
We estimated cumulative 5-year risks of CIN 3+ for 965,360 women aged 30 to 64 years undergoing cotesting at Kaiser Permanente Northern California over 2003 to 2010. We calculated the implicit risk thresholds for Pap-alone and applied them for new management guidance on HPV and Pap cotesting, citing 2 examples: HPV-positive/atypical squamous cells of undetermined significance (ASC-US) and HPV-negative/Pap-negative. We call this guidance process “benchmarking.”
A low-grade squamous intraepithelial lesion result, for which immediate colposcopy is prescribed, carries a 5-year CIN 3+ risk of 5.2%, suggesting that test results with similar risks should be managed with colposcopy. Similarly, ASC-US (2.6% risk) is managed with a 6- to 12-month follow-up visit and Pap-negative (0.26% risk) is managed with a 3-year follow-up visit. The 5-year CIN 3+ risk among women with HPV-positive/ASC-US was 6.8% (95% confidence interval = 6.2%–7.6%). This is greater than the 5.2% risk implicitly leading to referral for colposcopy, consistent with current management recommendations that women with HPV-positive/ASC-US be referred for immediate colposcopy. The 5-year CIN 3+ risk among women with HPV-negative/Pap-negative results was 0.08% (95% confidence interval = 0.07%–0.09%), far below the 0.26% implicitly required for a 3-year return and justifying a longer (e.g., 5-year) return.
Using the principle of “equal management of equal risks,” benchmarking to implicit risk thresholds based on Pap-alone can be used to achieve safe and consistent incorporation of cotesting.
The principles of “benchmarking” and “equal management of equal risk” are introduced to guide safe and consistent incorporation of human papillomavirus and Pap cotesting into cervical screening and management.
1Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, DHHS, Bethesda, MD; 2Albert Einstein College of Medicine, Bronx, NY; 3Regional Laboratory, Kaiser Permanente Northern California, Berkeley, CA; 4Information Management Services Inc., Calverton, MD; 5Women’s Health Research Institute, Division of Research, Kaiser Permanente Northern California, Oakland, CA; and 6Division of Gynecologic Oncology, Kaiser Permanente Medical Care Program, Oakland, CA
Reprint requests to: Hormuzd A. Katki, PhD, Division of Cancer Epidemiology and Genetics, National Cancer Institute, 6120 Executive Blvd Room 8014, EPS MSC 7244, Bethesda, MD 20882. E-mail: firstname.lastname@example.org; Walter K. Kinney, MD, Kaiser Permanente Northern California, Sacramento Medical Center, 1650 Response Rd, Sacramento, CA 95815. E-mail: email@example.com
Drs Schiffman and Gage report working with Qiagen, Inc, on independent evaluations of noncommercial uses of careHPV (a low-cost HPV test for low-resource regions) for which they have received research reagents and technical aid from Qiagen at no cost. They have received HPV testing for research at no cost from Roche. Dr Castle has received compensation for serving as a member of a Data and Safety Monitoring Board for HPV vaccines for Merck and also received HPV tests and testing for research at a reduced or no cost from Qiagen, Roche, MTM, and Norchip. Dr Castle is also a paid consultant for BD, GE Healthcare, and Cepheid and has received a speaker honorarium from Roche. The other authors have declared they have no conflicts of interest.
The Intramural Research Program of the US National Institutes of Health/National Cancer Institute and Kaiser Permanente Northern California reviewed the final article for publication. The Kaiser Permanente Northern California Institutional Review Board (IRB) approved use of the data, and the National Institutes of Health Office of Human Subjects Research deemed this study exempt from IRB review.