Descriptive epidemiology of gastric cancer in Costa Rica from 1990 to 2022 and projection of deaths to 2050: a population-based study.

Background: In Costa Rica, gastric cancer has been the leading cause of cancer death (both sexes) since the 1980s. The objective of this study was to analyze the incidence, mortality, and geographic distribution of stomach cancer in Costa Rica for the period 1990-2022, and to make projections of deaths up to 2050. Methods: Incidence and mortality data were from the Costa Rican National Cancer Registry, the Costa Rican National Institute of Statistics and Census, and the Central American Population Research Center. Age-standardized incidence and mortality rates, annual percent changes (APC), and years of potential life lost (YPLL) were calculated. Crude mortality rates were estimated at the canton level. Mortality projections were made using Poisson models. Findings: The standardized rates have been decreasing in all ages over 40 years old, in men and in women (in incidence, APC = -4.4% [-4.6, -4.3] in men, APC = -3.6% [-3.8, -3.3] in women; in mortality APC = -3.5% [-3.7, -3.4] in men, APC = -3.0% [-3.3, -2.8] in women). YPLL rates increased with age, but the age group with the highest number of YPLL was between 50 and 69 years. High mortality rates were observed in the mountainous areas east and south of the capital region, and one canton in Guanacaste. Most models projected increases in number of deaths of 50%-200% by the year 2050. Interpretation: Despite declining mortality rates, the number of gastric cancer deaths is projected to rise, underscoring the need for targeted public health strategies-particularly programs for Funding: The study was supported by the Agencia Costarricense de Investigaciones Biomédicas-Fundación INCIENSA.