RCT of EFTR Versus STER for GIST Treatment

Consecutive adult patients age \>=18 and \<=75 with a clinical diagnosis of gastric GIST who opted for endoscopic resection would be screened for eligibility. Inclusion Criteria: * Presence of gastric subepithelial tumor on diagnostic upper endoscopy, and * Diagnostic EUS and CT scan with intravenous contrast suspicious of GIST arising from muscularis propria layer, size with maximum diameter \>=1.0cm and \<= 3.5cm, and * Absence of high risk features, including irregular margins, invasion to surrounding organs, lesion hypervascularity, and * Endoscopic morphology and location deemed feasible with both EFTR and STER by an expert endoscopist, or * Histological confirmation of GIST through EUS guided fine needle biopsy (Optional, based on recommendation from guidelines) Exclusion Criteria: * Patients with tumors deemed not suitable for endoscopic resection (Either EFTR or STER), due to unfavourable location, high risk morphology, or any other reasons. * Patients with multiple tumors. * Patients unable or unwilling to provide consent. * Previous esophageal or gastric surgery. * Patients with significant cardiorespiratory comorbidities which may limit their ability to undertake general anesthesia for the procedure, including ASA grade III or above. * Pregnant women or those planning pregnancy or breastfeeding women. * Uncorrectable coagulopathy defined by international normalized ratio (INR) \> 1.5 or platelet count \< 50000/µl. * Patients on double anti-platelet agents or anti-coagulation (Warfarin, heparin or other direct oral anticoagulants)