Effectiveness of endoscopic screening for gastric cancer: The Japan Public Health Center-based Prospective Study.

Upper gastrointestinal endoscopy for gastric cancer screening has been implemented in Japan. However, its effectiveness for gastric cancer prevention has not been fully studied. We aimed to investigate the effectiveness of endoscopic screening to reduce mortality from gastric cancer. In a large prospective population-based cohort study including 80,272 participants, we compared the risk of mortality and incidence of gastric cancer among participants who underwent endoscopic or radiographic screening compared with those who did not undergo any screening using multivariable Cox proportional hazards models. In the 1,023,364 person-year observation period (median; 13.0 years), 1977 cases of gastric cancer were diagnosed, and 783 patients with gastric cancer died. In the endoscopic screening group, the mortality from gastric cancer and incidence of advanced gastric cancer were reduced by 61% (hazard ratio [HR] = 0.39 [95% CI: 0.30-0.51]) and 22% (HR = 0.78 [95% CI: 0.67-0.90]), respectively. The radiographic screening reduced the mortality from gastric cancer (HR = 0.63 [95% CI: 0.54-0.73]), but its effectiveness was lower than that of endoscopic screening. In conclusion, endoscopic screening reduced the incidence of advanced gastric cancer and mortality from gastric cancer in the Japanese population.