Socioeconomic, biological, and behavioral determinants of gastric cancer incidence and mortality in Latin America and the Caribbean: a sex-stratified ecological study with projections to 2050.

BACKGROUND: Gastric cancer imposes a heavy, geographically uneven burden across Latin America and the Caribbean. We quantified the associations of socioeconomic, biological, and behavioral factors with gastric cancer incidence and mortality across the region, examined sex-specific patterns and the projected burden to 2050. METHODS: A cross-sectional ecological study used the country as the unit of analysis. Age-standardized incidence and mortality rates for 2022 were drawn from the Global Cancer Observatory; behavioral and dietary exposures from the Global Burden of Disease 2021 study; socioeconomic indicators from the United Nations Development Programme; health expenditure from the World Health Organization; and Helicobacter pylori prevalence from a global systematic review. Ordinary least squares models with robust standard errors were fitted by sex, with false discovery rate correction. Projections of cases and deaths to 2050 were examined. RESULTS: The burden was geographically heterogeneous, with the highest rates in Chile, Colombia, Ecuador, and Peru. Cases and deaths were projected to rise 30-50% by 2050 in most countries. Educational inequality was the most consistent determinant, associated with higher mortality overall and with both incidence and mortality among women, in whom the Human Development Index and H. pylori prevalence were also relevant. CONCLUSION: Educational inequality and H. pylori prevalence were most consistently associated with the gastric cancer burden, particularly among women. POLICY SUMMARY: Reducing the gastric cancer burden in Latin America will require policies that address educational inequality as a structural driver, alongside H. pylori screen-and-treat programs, dietary sodium reduction, and early detection in high-burden Andean countries.