The Efficacy of Esomeprazole Premedication on Intraoperative Bleeding During Gastric ESD

Inclusion Criteria: * Ability to understand and the willingness to sign a written informed consent document. * Female or male aged ≥18 years. * Patients must have gastric mucosal lesion that are eligible for ESD indications (Japanese Gastric Cancer Association 2011), including early gastric cancer, polyps, adenoma, and precancerous/suspected lesions diagnosed by endoscopy. Exclusion Criteria: * Malignancy or other advanced disease with a life expectancy of \< 6 months as judged by the investigator. * The ASA classification of physical status ≥ 4 as judged by the investigator. * Severe hepatic disease or renal disease * Ability to understand and the willingness to sign a written informed consent document. * Major cardiovascular event at enrollment or within 3 months prior to enrollment such as stroke, myocardial infarction, or hospitalization for treatment of unstable angina pectoris as judged by the investigator. * Haemorrhagic disorder. * Patients who had a history of gastrectomy or a recurrent lesion. * Known or suspected hypersensitivity to any component of any PPI . * Planned treatment with: warfarin (including other vitamin K antagonists), cisapride, phenytoin, atazanavir, nelfinavir, digoxin, methotrexate, clopidogrel, tacrolimus, theophylline, lidocaine, nifedipine. * Pregnancy, planned pregnancy or lactation. Women of childbearing potential must use reliable and medically accepted methods of birth control, as judged by the investigator. * Known or suspected alcohol, drug or medication abuse. * Any condition associated with poor compliance as judged by the investigator. * Participation in any study involving administration of an investigational product or device within the preceding 14 days prior to enrollment. * Involvement in the planning and conduct of the study. Previous enrollment in the present study.