Early Mortality Following Systemic Anticancer Therapy in Lung Cancer: A Bayesian Spatiotemporal Multilevel Analysis

Introduction Despite advances in lung cancer treatment, early mortality following Systemic Anticancer Therapy (SACT) remains a major concern. Identifying patients at high risk of early mortality may inform treatment decision‐making, particularly where SACT may offer limited benefit. We aimed to quantify spatiotemporal patterns of early mortality following SACT and to examine the relative contributions of individual‐ and area‐level risk factors. Methods We conducted a secondary analysis of data from the Victorian Lung Cancer Registry. Bayesian spatiotemporal multilevel models were used to assess associations between individual‐ and area‐level factors and early mortality following SACT. Adjusted Odds Ratios (AORs) with 95% Credible Interval (Crl) were reported to indicate statistical significance. Results Substantial spatiotemporal variation in early mortality following SACT was observed across Victoria. Factors associated with increased odds of early mortality included age ≥ 60 years (AOR = 1.06, 95% Crl: 1.01–1.22), clinical stage II (AOR = 1.15, 95% Crl: 1.01–1.59), stage III (AOR = 1.28, 95% Crl: 1.01–2.05), stage IV (AOR = 3.19, 95% Crl: 2.12–5.07), comorbidity (AOR = 1.12, 95% Crl: 1.01–1.34), and poor performance status (AOR = 3.09, 95% Crl: 2.24–4.24). Presentation at a multidisciplinary meeting (AOR = 0.66, 95% Crl: 0.52–0.88) and receipt of supportive care screening (AOR = 0.53, 95% Crl: 0.41–0.69) were associated with reduced odds of early mortality. Conclusion Marked spatiotemporal variation in early mortality following SACT highlights the need for targeted, risk‐informed treatment strategies, particularly for patients with advanced disease, comorbidities, poor performance status, and those residing in high‐risk areas.