Endosonography-Guided Fine-Needle Aspiration versus "Key-Hole Biopsy" in the diagnostics of upper gastrointestinal subepithelial tumors. A prospective randomized interventional study.

Background: The management and prognosis of subepithelial tumors (SETs) of the upper gastrointestinal tract depend on the correct preoperative evaluation, including tissue diagnosis in selected cases. Several methods providing deep tissue sampling for cytological and/or histological examinations have been described but their diagnostic yield and precise position in the diagnostic algorithm remain to be established. This prospective randomized study aims to compare the Endosonography-Guided Fine-Needle Aspiration (EUS-FNA) to Key-Hole Biopsy (KHB) in cytological or histological diagnostics of upper gastrointestinal SETs.