Long-term use of proton pump inhibitors does not affect ectopic and metachronous recurrence of gastric cancer after endoscopic treatment

Objective: Long-term administration of proton pump inhibitors (PPIs) after eradication of Helicobacter pylori infection has been reported to increase the risk for development of gastric cancer (GC). We investigated whether long-term administration of PPI affects ectopic and metachronous recurrence of GC after endoscopic treatment. Methods: Participants were 687 patients who underwent endoscopic treatment for GC from January 2005 to March 2018. Questionnaire surveys and medical record reviews of medications, including PPIs, H-2 receptor antagonists and low-dose aspirin (LDA) were conducted for all patients. The influence of PPI in ectopic and metachronous recurrence of GC was evaluated with Cox's proportional hazard analysis. Results: Patients who did not respond to the questionnaire and those who underwent additional treatment after endoscopic treatment were excluded from analyses; 418 patients were included. During an average observation period of 1608 days (range, 375-4993 days), 136 patients (32.5%) took PPIs for more than 1 year and 94 took PPIs for more than 3 years; of those, 40 had ectopic and metachronous recurrences. Cox's proportional hazards analysis revealed that long-term use of PPIs (for both 1 year and 3 years) was not a risk factor for recurrence. In addition, age, severity of gastric atrophy, long-term use of LDA, current infection with H. pylori, and cure achieved with the first endoscopic treatment were also not risk factors for recurrence. Conclusions: Long-term use of PPIs does not affect ectopic and metachronous recurrence of GC after endoscopic treatment.