Aim: This study evaluates how recent changes in Australia’s cervical screening program and the rollout of FOBT screening for colorectal cancer have influenced incidence and diagnostic patterns in Queensland. A key objective is to understand whether these programs have produced measurable shifts in stage at diagnosis, alongside reductions in incidence driven by prevention.
Methods: This data linkage project was a collaboration between Cancer Alliance Queensland and Queensland Health Cancer Screening Unit. Analysis focused on individuals diagnosed with cervical or colorectal cancer between 2015-2024. Those included were women aged 25-69 (cervical) and people aged 50-74 (colorectal), in-line with target ages for these national screening programs.
Results: Cervical: Three-quarters (75%) of cases were diagnosed in individuals who were under‑screened or never screened. Greater screening participation corresponded to a shift toward earlier stage, as evidenced by a 33% reduction in locally advanced or metastatic disease since 1999. The transition to HPV‑based screening increased sensitivity, reflected in higher rates of abnormal preceding results and likely causing a temporary rise in incidence during 2018–2020. Incidence in the latest years has returned to 2015 levels and is declining further.
Colorectal: Over 17,000 people aged 50-74 were diagnosed with colorectal cancer over the 10-year period, though the incidence rate dropped by over 20% during this time. Only 21% of 2015 diagnoses were among people who participated in screening, compared with 35-40% in later years, reflecting the maturity and expanded rollout of the screening program. Non-participants were more likely to have a diagnosis of advanced cancer (regional nodal spread, or metastatic cancer: %) compared with screening participants (25%).
Conclusion: Screening programs have successfully lowered incidence rates and resulted in earlier stage for both cervical and colorectal cancer. Strengthened collaboration between the National Cancer Screening Register and cancer registries will enhance surveillance of interval cancers and program performance.