Abstract
Background and study aims Currently, gastric cancer screening is only cost-effective in countries with high incidence. Integrated screening, in which gastroscopy is performed in conjunction with colonoscopy, could help reduce the gastric cancer screening procedure burden in countries with low or intermediate incidence. However, there is a lack of population-based studies to identify high-risk groups. Methods In this retrospective analysis of a colorectal cancer (CRC) screening program database, we used Cox proportional hazards model to identify an association of high- and low-risk finding (polyps ≥ 10 mm or with high-grade dysplasia) with time to death from upper gastrointestinal cancer (esophageal and gastric). We estimated the 10-year mortality of upper gastrointestinal tumors in different 10-year age groups, stratified by sex and polyp finding at colonoscopy. Results We included 349,856 CRC screening colonoscopies in our study. The median follow-up time was 5.22 years (95% confidence interval [CI] 5.21-5.24 years). Of the participants, 4.5% had polyps ≥ 10 mm or with high-grade dysplasia (HGD). At the end of the study period, 384 deaths from upper gastrointestinal cancer had occurred. Aside from age and sex, we found the presence of high-risk polyps to be significantly associated with upper gastrointestinal cancer death (hazard ratio 1.54, 95% CI 1.06-2.25, P = 0.025). Conclusions CRC screening participants with polyps < 10 mm and no HGD have a lower risk for mortality from upper gastrointestinal cancers compared with participants with polyps > 10 mm and HGD. Future studies will demonstrate whether integrated screening with additional gastroscopy is effective in CRC screening participants with large or highly dysplastic polyps.