One cancer, two stories: divergent estimates of gastric cancer burden in Korea.

backgroundGlobal Burden of Disease (GBD) estimates are widely used for international health comparisons, but their validity in high-data settings remains debated. Gastric cancer provides a critical case, given its high incidence in East Asia and the availability of robust national screening and mortality data.

methodsWe compared estimates from the Korean National Burden of Disease (KNBD) study and the GBD for gastric cancer between 2008 and 2018. We additionally examined Japan, another country with nationwide gastric cancer screening and high-quality mortality reporting, to assess whether similar patterns emerged.

resultsKNBD reported declines in years of life lost (YLLs), reflected in the decreasing YLL share of disability-adjusted life years (DALYs), alongside substantial increases in years lived with disability (YLDs), underscoring survivorship-related disability. By contrast, GBD Korea showed a decrease in YLL but virtually no change in YLD. In Japan, where mortality has also declined substantially through national screening programs, GBD nevertheless reported negligible changes in YLL and YLD shares of total DALYs. Although a Japanese national DALY study is not available for direct comparison, these similar patterns across GBD Korea and GBD Japan raise concerns about the capacity of GBD methods to adequately capture survivorship in high-data countries.

conclusionOur findings demonstrate that the same disease can generate fundamentally different burden-of-disease narratives depending on the metric framework applied. In Korea, national data highlight survivorship-related disability that is effectively absent in GBD estimates; in Japan, GBD may similarly downplays disability despite declining mortality. Policymakers may consider national burden-of-disease estimates as more appropriate for local planning, while global models could be strengthened by integrating high-quality country-level data to better reflect survivors' burdens.