A study of HPV typing for the management of HPV-positive ASC-US cervical cytologic results

• HPV genotyping might be useful as part of ASC-US triage.
• The absence of the highest-risk genotypes reduces risk sufficiently to consider one-year retesting.
• A fifth of colposcopy referrals might be avoided with little delay in diagnosis of CIN3 or worse lesions.

BackgroundIn US cervical screening, immediate colposcopy is recommended for women with HPV-positive ASC-US (equivocal) cytology. We evaluated whether partial typing by Onclarity™ (BD) might identify HPV-positive women with low enough CIN3+ risk to permit 1-year follow-up instead.MethodsThe NCI-Kaiser Permanente Northern California Persistence and Progression cohort includes a subset of 13,890 women aged 21+ with HC2 (Qiagen)-positive ASC-US at enrollment; current median follow-up is 3.0 years. Using stratified random sampling, we typed 2079 archived enrollment specimens including 329 women subsequently diagnosed with CIN3+, 563 with CIN2, and 1187 with < CIN2. Adjusting for sampling, we computed 3-year cumulative CIN3+ risks for each Onclarity typing channel, using Kaplan–Meier methods.ResultsThe 3-year CIN3+ risk for all HC2-positive women with ASC-US was 5.2%; this establishes the “benchmark” risk for colposcopic referral. Hierarchically, 3-year cumulative risks for each typing channel were 16.0% for HPV16, 7.4% for HPV18, 7.0% for HPV31, 7.1% for grouped HPV33/58, 4.3% for HPV52, 3.9% for HPV45, 2.7% for HPV51, 1.6% for HPV39/68/35, and 1.3% for HPV59/56/66.DiscussionASC-US linked to HPV16, HPV18, HPV31, or HPV33/58 warrants immediate colposcopy. Optimal management of women with HPV52 or HPV45 is uncertain. Risk of women with only HPV51, HPV39/68/35, or HPV59/56/66 might be low enough to recommend 1-year retesting permitting viral clearance. This strategy would defer colposcopy for 40% of women with HPV-positive ASC-US, half of whom would be cotest-negative at 1-year return. Approximately 10% of those with CIN3 diagnosable at enrollment would be delayed 1 year instead. Cost-effectiveness analyses are needed.