BACKGROUND AND AIMS This study stratified the risk of developing metachronous gastric cancer (MGC) after curative endoscopic submucosal dissection (ESD) of early gastric cancer (EGC) to enable customization of endoscopic surveillance for MGC.

METHODS A total of 1115 patients who underwent curative ESD based on the expanded criteria for differentiated EGC from 2005 to 2014 at a single tertiary hospital were enrolled in this retrospective cohort study. They were followed up with annual endoscopy for a median of 50.1 months. Helicobacter pylori and histologic intestinal metaplasia (IM) were evaluated. The Kaplan-Meier method and Cox regression analysis were used for risk stratification.

RESULTS Three risk groups were identified: group 1 comprised patients with a synchronous neoplasm; group 2 comprised male patients with corpus IM; and group 3 comprised male patients without corpus IM or female patients. The 5- and 7-year cumulative risks (95% confidence interval [CI]) for metachronous recurrence were 15.1% (95% CI, 7.7-22.5) and 26.1% (95% CI, 14.9-37.3), respectively, in group 1; 5.6% (95% CI, 3.1-8.1) and 9.3% (95% CI, 5.4-13.2), respectively, in group 2; and 3.8% (95% CI, 1.6-6.0) and 4.9% (95% CI, 2.4-7.4), respectively, in group 3 (P < .001 by log-rank test). The incidence of MGCs increased constantly even after 5 years in groups 1 and 2 but not in group 3. There was not enough evidence to show an association between H pylori eradication and metachronous recurrence in the data.

CONCLUSIONS Meticulous annual endoscopic surveillance for MGC for more than 5 years is recommended for patients with synchronous neoplasm. Endoscopic surveillance may also be extended beyond 5 years in male patients with corpus IM.