Aspirin Use Is Not Associated with the Risk of Metachronous Gastric Cancer in Patients without Helicobacter pylori Infection

Introduction: Helicobacter pylori (H. pylori) eradication can prevent metachronous gastric cancer (MGC) after the performance of an endoscopic resection for early gastric cancer (EGC). However, 50% of infections persist after eradication, and the identification of MGC protective factors is important. The anti-tumor activity of aspirin has been demonstrated, but its efficacy in preventing MGC remains controversial. We evaluated the effect of aspirin on metachronous recurrence in H. pylori-negative patients. Methods: A total of 4351 patients were evaluated between January 2007 and December 2016, and 2151 patients who met the inclusion criteria were analyzed. The primary outcome was the cumulative incidence of MGC after an endoscopic resection for EGC. Results: During a 5-year median follow-up (interquartile range, 3.5-6.2), MGC developed in 176 (7.7%) patients, with a cumulative incidence of 89.4% in aspirin users and 92.7% in non-users; this difference was not statistically significant (p = 0.64). The duration of aspirin uses and the occurrence of MGC in both groups were not significantly different. There was no significant difference between groups when the duration of aspirin use was categorized into <= 1 year (hazard ratio (HR), 0.64; 0.20-2.01, p = 0.45), 1-4 years (HR, 1.35; 0.66-2.76, p = 0.41), and >4 years (HR, 1.17; 0.67-2.03, p = 0.58). Conclusions: Aspirin use was not associated with a lower risk of MGC in H. pylori-negative patients. Further prospective studies are needed.

Automated summary

Aspirin use was not associated with a lower risk of metachronous gastric cancer in H. pylori-negative patients.