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Australia introduced COVID-19 infection prevention and control measures in early 2020. To help prepare health services, the Australian Government Department of Health commissioned a modelled evaluation of the impact of disruptions to population breast, bowel, and cervical cancer screening programmes on cancer outcomes and cancer services. We used the Policy1 modelling platforms to predict outcomes for potential disruptions to cancer screening participation, covering periods of 3, 6, 9, and 12 mo. We estimated missed screens, clinical outcomes (cancer incidence, tumour staging), and various diagnostic service impacts. We found that a 12-mo screening disruption would reduce breast cancer diagnoses (9.3% population-level reduction over 2020–2021) and colorectal cancer (up to 12.1% reduction over 2020–21), and increase cervical cancer diagnoses (up to 3.6% over 2020–2022), with upstaging expected for these cancer types (2, 1.4, and 6.8% for breast, cervical, and colorectal cancers, respectively). Findings for 6–12-mo disruption scenarios illustrate that maintaining screening participation is critical to preventing an increase in the burden of cancer at a population level. We provide programme-specific insights into which outcomes are expected to change, when changes are likely to become apparent, and likely downstream impacts. This evaluation provided evidence to guide decision-making for screening programmes and emphasises the ongoing benefits of maintaining screening in the face of potential future disruptions.

Background: Australia's National Cervical Screening Program currently recommends cytological screening every 2 years for women aged 18–69 years. Human papillomavirus (HPV) vaccination was implemented in 2007 with high population coverage, and falls in high-grade lesions in young women have been reported extensively. This decline prompted a major review of the National Cervical Screening Program and new clinical management guidelines, for which we undertook this analysis. Methods: We did effectiveness modelling and an economic assessment of potential new screening strategies, using a model of HPV transmission, vaccination, natural history, and cervical screening. First, we evaluated 132 screening strategies, including those based on cytology and primary HPV testing. Second, after a recommendation was made to adopt primary HPV screening with partial genotyping and direct referral to colposcopy of women positive for HPV16/18, we evaluated the final effect of HPV screening after incorporating new clinical guidelines for women positive for HPV. Both evaluations considered both unvaccinated and vaccinated cohorts. Findings: Strategies entailing HPV testing every 5 years and either partial genotyping for HPV16/18 or cytological co-testing were the most effective. One of the most effective and cost-effective strategies comprised primary HPV screening with referral of women positive for oncogenic HPV16/18 direct to colposcopy, with reflex cytological triage for women with other oncogenic types and direct referral for those in this group with high-grade cytological findings. After incorporating detailed clinical guidelines recommendations, this strategy is predicted to reduce cervical cancer incidence and mortality by 31% and 36%, respectively, in unvaccinated cohorts, and by 24% and 29%, respectively, in cohorts offered vaccination. Furthermore, this strategy is predicted to reduce costs by up to 19% for unvaccinated cohorts and 26% for cohorts offered vaccination, compared with the current programme. Interpretation: Primary HPV screening every 5 years with partial genotyping is predicted to be substantially more effective and potentially cost-saving compared with the current cytology-based screening programme undertaken every 2 years. These findings underpin the decision to transition to primary HPV screening with partial genotyping in the Australian National Cervical Screening Program, which will occur in May, 2017. Funding: Department of Health, Australia.

BACKGROUND:Several countries are implementing a transition to HPV testing for cervical screening in response to the introduction of HPV vaccination and evidence indicating that HPV screening is more effective than cytology. In Australia, a 2017 transition from 2-yearly conventional cytology in 18-20 to 69 years to 5-yearly primary HPV screening in 25 to 74 years will involve partial genotyping for HPV 16/18 with direct referral to colposcopy for this higher risk group. The objective of this study was to determine the optimal management of women positive for other high-risk HPV types (not 16/18) ('OHR HPV'). METHODS:We used a dynamic model of HPV transmission, vaccination, natural history and cervical screening to determine the optimal management of women positive for OHR HPV. We assumed cytology triage testing was used to inform management in this group and that those with high-grade cytology would be referred to colposcopy and those with negative cytology would receive 12-month surveillance. For those with OHR HPV and low-grade cytology (considered to be a single low-grade category in Australia incorporating ASC-US and LSIL), we evaluated (1) the 20-year risk of invasive cervical cancer assuming this group are referred for 12-month follow-up vs. colposcopy, and compared this to the risk in women with low-grade cytology under the current program (i.e. an accepted benchmark risk for 12-month follow-up in Australia); (2) the population-level impact of the whole program, assuming this group are referred to 12-month surveillance vs. colposcopy; and (3) the cost-effectiveness of immediate colposcopy compared to 12-month follow-up. Evaluation was performed both for HPV-unvaccinated cohorts and cohorts offered vaccination (coverage ~72%). FINDINGS:The estimated 20-year risk of cervical cancer is ≤1.0% at all ages if this group are referred to colposcopy vs. ≤1.2% if followed-up in 12 months, both of which are lower than the ≤2.6% benchmark risk in women with low-grade cytology in the current program (who are returned for 12-month follow-up). At the population level, immediate colposcopy referral provides an incremental 1-3% reduction in cervical cancer incidence and mortality compared with 12-month follow-up, but this is in the context of a predicted 24-36% reduction associated with the new HPV screening program compared to the current cytology-based program. Furthermore, immediate colposcopy substantially increases the predicted number of colposcopies, with >650 additional colposcopies required to avert each additional case of cervical cancer compared to 12-month follow-up. Compared to 12-month follow-up, immediate colposcopy has an incremental cost-effectiveness ratio (ICER) of A$104,600/LYS (95%CrI:A$100,100-109,100) in unvaccinated women and A$117,100/LYS (95%CrI:A$112,300-122,000) in cohorts offered vaccination [Indicative willingness-to-pay threshold: A$50,000/LYS]. CONCLUSIONS:In primary HPV screening programs, partial genotyping for HPV16/18 or high-grade triage cytology in OHR HPV positive women can be used to refer the highest risk group to colposcopy, but 12-month follow-up for women with OHR HPV and low-grade cytology is associated with a low risk of developing cervical cancer. Direct referral to colposcopy for this group would be associated with a substantial increase in colposcopy referrals and the associated harms, and is also cost-ineffective; thus, 12-month surveillance for women with OHR HPV and low-grade cytology provides the best balance between benefits, harms and cost-effectiveness.