Pilot Study of Non-exposure Simple Suturing EFTR With Sentinel Lymph Node Navigation for EGC (Senorita3-pilot)

Inclusion Criteria: * single lesion of adenocarcinoma in preoperative endoscopic biopsy * clinical stage T1N0 in the preoperative evaluation of endoscopy and computed tomography * tumor size: less than 3cm in differentiated type, less than 2cm in undifferentiated type * location: 2cm far from the pylorus or cardia * aged 20 to 80 * ECOG 0 or 1 * patient who signed the agreement * patient who is suspected to underwent laparoscopy assisted gastrectomy Exclusion Criteria: * indication of endoscopic submucosal resection * inoperable due to poor cardiac, pulmonary function * pregnant * having allergic reaction, previous upper abdominal surgery except laparoscopic cholecystectomy, previous radiation therapy to upper abdomen * diagnosed as malignancy within 5 years except carcinoma in situ of cervix cancer and thyroid cancer