Optimising management of women with HPV (not 16/18): Findings from a national HPV screening program

Australian guidelines updated in 2021 recommend a second 12-month follow-up HPV test, instead of immediate colposcopy, for participants with HPV (not 16/18) and negative/low-grade cytology at both primary screening and 12-month follow-up (excepting Aboriginal and/Torres Strait Islander women, those aged ≥50 years or ≥2 years overdue for primary screening). We examined the safety of this change using naturally-occurring variation in colposcopy timing after a 12-month follow-up test.

Using National Cancer Screening Register data (December 2017-April 2022), we employed Kaplan-Meier analyses to estimate the cumulative incidence of serious cervical abnormalities in those with colposcopy within six months (immediate) versus 12-18 months (deferred) after 12-month follow-up. Analyses were restricted to women who, at their primary screening test, were aged 25-69 years and not ≥2 years overdue, and stratified by age group, Indigenous status, socio-economic status, state/territory, and year of primary screening.

Among 31,499 women with immediate colposcopy and 2562 with deferred colposcopy, the cumulative incidence of cervical intraepithelial neoplasia grade 3 or worse was slightly higher at 24 months in the deferred group (8.3 %; 95 % CI: 6.9-9.9 %) compared to the immediate group (5.7 %; 95 % CI: 5.3-6.0 %). By 36 months, the difference was small and not significant (deferred: 11.3 %; 95 % CI: 8.6-14.7 % vs immediate: 9.9 %; 95 % CI: 8.8-11.2 %). Similar patterns were observed in stratified analyses, except for Aboriginal and Torres Strait Islander women, where a difference persisted to 36 months (deferred: 28.1 %; 95 % CI: 13.4-52.9 % vs immediate: 7.0 %; 95 % CI: 4.4-11.0 %).

Our findings support the safety of updated guidelines for deferring colposcopy and the different recommendation for Aboriginal and Torres Strait Islander women. Although these data do not directly support the different recommendation for those aged ≥50 years, longer follow-up studies are required, given the potential for delayed detection of covert canal lesions in this age group.