Nationwide oral cancer screening and rural-urban disparities in oral cancer diagnosis, treatment and mortality: a population-based cohort study in Taiwan

Background This study assesses the association between Taiwan’s national oral cancer screening (OCS) programme and rural-urban disparities in late-stage diagnosis, treatment delays and mortality among oral cavity cancer (OCC) patients. Methods A retrospective cohort study was conducted using data from the Taiwan National Cancer Registry and National Health Insurance databases, including 16 430 OCC patients diagnosed between 2010 and 2013, with follow-up through 2018. Results Among urban patients, OCS was associated with a lower likelihood of late-stage diagnosis (AOR=0.86, 95% CI 0.80 to 0.92, p<0.01) but a higher likelihood of treatment delay (AOR=1.09, 95% CI 1.00 to 1.19, p=0.04). Unscreened rural patients were more likely to be diagnosed at a late stage (AOR=1.35, 95% CI 1.05 to 1.74, p=0.02), whereas no statistically significant association was observed among screened rural patients (AOR=0.93, 95% CI 0.73 to 1.18, p=0.54). Conclusions Rural-urban disparities in late-stage diagnosis and mortality among OCC patients persist in Taiwan. While OCS was associated with fewer late-stage diagnoses in both urban and rural patients, these benefits were more evident among urban patients. No significant reduction in rural-urban mortality disparities was observed. Comprehensive strategies, including strengthening rural diagnostic and treatment capacity, are needed to reduce these disparities.