Excess mortality from gastric cancer in Korea during the COVID-19 pandemic, 2020-2023.

The coronavirus disease 2019 (COVID-19) pandemic substantially disrupted cancer care, leading to declines in screening, diagnosis, and treatment. Gastric cancer is particularly vulnerable to such disruptions because reductions in mortality depend largely on early detection and timely treatment. This study estimated excess mortality from gastric cancer in Korea during the COVID-19 pandemic. Expected gastric cancer deaths during the pandemic were estimated by applying linear regression to age-specific mortality trends from 2015 to 2019. Excess mortality was quantified using annual P-scores. Gastric cancer mortality declined steadily before the pandemic, but this decline attenuated during the pandemic period. Annual P-scores increased progressively, from +3.8% in 2020 and +5.5% in 2021 to +10.6% in 2022 and +20.7% in 2023. By age group, individuals aged 60-79 years showed the largest increases, reaching +46.6% in 2023, whereas minimal excess mortality was observed among those aged 20-59 years. Among adults aged ≥80 years, excess mortality became apparent only in 2023 (+12.8%). Overall, a progressive increase in excess mortality due to gastric cancer was observed in Korea during the COVID-19 pandemic, particularly among individuals aged 60-79 years. These findings suggest that the pandemic adversely affected gastric cancer control and underscore the need for continued monitoring.