Incidence of Metachronous Gastric Cancer After Endoscopic Submucosal Dissection in Helicobacter pylori-uninfected Early Gastric Cancer.

PURPOSE: Helicobacter pylori (H. pylori)-associated gastric cancer can progress to metachronous gastric cancer even after eradication; however, the incidence of metachronous gastric cancer in H. pylori-uninfected cases remains unclear. We aimed to investigate the incidence of metachronous gastric cancer after endoscopic submucosal dissection (ESD) in H. pylori-uninfected patients.

METHODS

This single-center retrospective cohort study included 850 consecutive patients with gastric cancer (850 lesions) who underwent ESD between January 2010 and December 2021. The primary endpoint was the first metachronous gastric cancer detected more than 1 year after ESD. The secondary endpoint was synchronous gastric cancer detected within 1 year of ESD.

RESULTS

In total, 38 and 812 of the patients were H. pylori-uninfected and H. pylori-infected, respectively. Synchronous gastric cancer was less frequent in the H. pylori-uninfected group (0% vs. 7.0%), although the difference was not significant (p = 0.103). Metachronous gastric cancer was significantly less frequent in the H. pylori-uninfected group (0% vs. 16.9%, p = 0.002), and the cumulative incidence was significantly lower (p = 0.011). In exploratory multivariable Firth's penalized Cox regression analyses, H. pylori-uninfected status remained associated with a lower estimated risk of metachronous gastric cancer, although the association did not reach statistical significance.

CONCLUSIONS

The incidence of metachronous gastric cancer after ESD for early gastric cancer is lower in H. pylori-uninfected patients than in H. pylori-infected patients. Although these findings should be interpreted as exploratory, they suggest that the optimal post-ESD surveillance strategy for H. pylori-uninfected patients warrants further investigation.