A 71-year-old man was referred to us from another hospital for endoscopic treatment of a IIc lesion at the anterior wall of the lower body of the stomach. In November 2008, he underwent resection of this lesion with endoscopic submucosal dissection (ESD). Follow-up endoscopy revealed a IIc lesion in the posterior wall of the lower body of the stomach, and ESD was again performed in February 2009. At the same time, Helicobacter pylori was detected, and successful first-line eradication therapy was verified in May 2009. Subsequent follow-up endoscopy detected multiple ectopic and metachronous gastric cancers at three sites, all of which were endoscopically resected (quintuple gastric cancer). Although ectopic and metachronous recurrence of gastric cancer was detected immediately after H. pylori eradication, recurrence of gastric cancer has not been detected in the 5 years since eradication. Future directions include determining the time point at which the preventative effects of H. pylori eradication therapy appear against gastric cancer recurrence. We report our findings herein, along with a review of the related literature.