BJOG. 2022 Aug 25. doi: 10.1111/1471-0528.17284. Online ahead of print.
OBJECTIVE: To understand the effect of changing from cytology-based to primary HPV screening on the positive predictive value (PPV) of colposcopy referrals for cervical intraepithelial neoplasia (CIN) in a cohort offered HPV vaccination.
DESIGN: Retrospective pre/post observational cohort study.
SETTING: Scotland POPULATION OR SAMPLE: 2193 women referred to colposcopy between September 2019 – February 2020 from cytology-based screening and September 2020 – February 2021 from primary high-risk HPV (hrHPV) screening.
METHODS: Calculating Positive Predictive Values (PPVs) for 2 cohorts of women; one having liquid-based cytology screening and the subsequent high-risk HPV hrHPV cervical screening as a pre/post observational study.
MAIN OUTCOME MEASURES: Positive predictive values of LBC and hrHPV cut-offs for colposcopy referral for CIN at colposcopy.
RESULTS: Narrative review: Three papers fitted our criteria; these reported results only for cytology-based screening. The PPV was lower for women in HPV vaccinated cohorts indicating the lower prevalence of disease. Vaccination underage of 17 had the lowest PPV reported. Scottish colposcopy data: hrHPV and cytology showed a non-significant difference between PPV (17.5%, CI 95%=14.3-20.7; 20.6, CI 95%=16.7-24.5) for referrals with a cut-off of low grade dyskaryosis (LGD); both met the standard set of 8-25%. hrHPV PPV (66.7, CI 95%=56.8-76.6) was comparable to cytology (64.1, CI 95%=55.8-72.4) for referrals with a cut-off of high grade dyskaryosis (HGD) but neither met the standard set of 77-92%.
CONCLUSIONS: Current literature only provided PPVs for LBC and overall, the vaccinated cohort had lower PPVs. Only LG dyskaryosis met PHE criteria. The PPV for HPV vaccinated women undergoing either LBC or HR-HPV screening were not statistically different. However, similar to the papers in current literature, HG dyskaryosis (HGD) PPVs of both techniques did not meet the PHE threshold of 76.6-91.6% outlined in the cervical standards data report..