Objective: High-grade Pap results (e.g., atypical glandular cells [AGC], atypical squamous cells cannot rule out HSIL [ASC-H], and high-grade squamous intraepithelial lesion [HSIL]) predict high cancer risks, resulting in referral for colposcopy without HPV triage. However, new guidelines recommending cotesting for women 30 years and older imply that clinicians will often receive the HPV test result concurrently for high-grade Pap results. We examined whether HPV testing provides useful risk stratification in this context.
Methods: From a cohort of 965,360 women aged 30 to 64 years undergoing cotesting at Kaiser Permanente Northern California, we estimated 5-year risks for cervical cancer and CIN 3+ after AGC (2,074 women), ASC-H (1,647 women), and HSIL (2,019 women) according to HPV test results.
Results: HPV positivity of AGC Pap results was 25% and decreased with age (30 to 34 vs 60 to 64 years, 44% vs 17%, p < .0001), whereas HPV positivity of ASC-H and HSIL was much higher (71% and 94%) and decreased less with age. Even for these high-grade Pap results, 5-year CIN 3+ risks differed substantially between HPV-positive and HPV-negative women (AGC, 33% vs 0.93%, p < .0001; ASC-H, 25% vs 3.5%, p < .0001; HSIL, 49% vs 30%, p = .006). However, except for AGC, cervical cancer risks differed less between HPV-positive and HPV-negative women (AGC, 9.0% vs 0.37%, p < .0001; ASC-H, 2.5% vs 2.1%, p = .8; HSIL, 6.6% vs 6.8%, p = .7).
Conclusions: The risks of CIN 3+ among women with HPV-negative high-grade Pap results were lower than those among women with HPV-positive high-grade Pap results, especially after AGC. However, by the principle of “equal management of equal risks,” all HPV-negative high-grade Pap results had cancer risks high enough to warrant colposcopy, confirming that there is no current role for HPV triage of high-grade Pap results.