After endoscopic resection (ER) of gastric tumors, eradication of Helicobacter pylori (H. pylori) infection is advised to reduce metachronous recurrence. However, few studies have addressed factors influencing H. pylori eradication rates in the aftermath of ER, and none have focused on the optimal timing of therapy to eradicate H. pylori post-ER.Therefore, the investigators will conduct to evaluate whether differences in timing of eradication therapy after ER of gastric tumors.