Comparison of Proton Pump Inhibitor and H2 Receptor Blocker on Prevention of Bleeding From Iatrogenic Ulcer After Endoscopic Submucosal Dissection for Gastric Neoplasms: A Prospective Randomized Controlled Trial

Inclusion Criteria: * the patients who agreed informed consent * gastric adenoma or early gastric cancer which is eligible for conventional ESD indication Exclusion Criteria: * recent drug history of PPI, H2 rector antagonist, bismuth and antibiotics within 4 weeks * recent drug history of anticoagulant or antiplatelet agent within 7 days * s/p subtotal gastrectomy * recurred gastric adenoma or cancer * pregnant or breast feeding patients