Prior gastroscopy and mortality in patients with gastric cancer: a matched retrospective cohort study

Background and Aims: The role of prior gastroscopy on the outcome of patients with gastric cancer remains unknown. This study determines the association between intervals of prior gastroscopy and mortality in patients with gastric cancer. Methods: We identified 20,066 newly diagnosed patients with gastric cancer in the National Health Insurance Database of Taiwan between 2002 and 2007. After we excluded patients who had gastroscopies performed <= 6 months before the diagnosis of cancer, patients were matched into 3 cohorts according to the intervals of prior gastroscopy: 6 months to 2 years (<2 Y cohort), 2 to 5 years (2-5 Y cohort), and none within the previous 5 years (> 5 Y cohort). The 3 cohorts were matched for age, curative treatment for gastric cancer, Helicobacter pylori therapy, and propensity scores comprised of sex, comorbidities, and concomitant medication usage. The primary outcome is the hazard ratio (HR) of all-cause mortality. Results: After matching, we identified 1286, 1286, and 5144 patients for the <2 Y, 2 to 5 Y, and > 5 Y cohorts. Compared with the > 5 Y cohort, the HR of all- cause mortality for the <2 Y and 2 to 5 Y cohorts was 0.80 (95% confidence interval [CI], 0.72-0.89; P < .001) and 0.83 (95% CI, 0.76-0.91; P < .001), respectively. The HRs of gastric cancer- specific mortality were significantly lower in the < 2 Y (0.80; 95% CI, 0.71-0.91; P < .001) and 2 to 5 Y cohorts (0.83; 95% CI, 0.75-0.93; P < .001). Conclusions: Patients with gastric cancer who had a gastroscopy performed within 5 years before the cancer diagnosis had significantly lower mortality. Our results may support the role of repeat endoscopic examination or surveillance endoscopy in selected patients.