Endoscopic Vacuum Therapy for Transmural Defects in the Upper Gastrointestinal Tract

The goal of this observational study is to learn about the best indications and techniques regarding endoscopic vacuum therapy (EVT) in patients with a transmural defect in the upper gastrointestinal (GI) tract (e.g. anastomotic leakage, Boerhaave syndrome, iatrogenic perforation, other). The main questions it aims to answer are: * What is the success rate of EVT for transmural defects in the upper GI tract? * What are the best indications for EVT in the upper GI tract? (e.g. etiology, patient characteristics, defect characteristics) * What are the best techniques for EVT in the upper GI tract? (e.g. EsoSponge, VACStent, vacuum pressure, intraluminal/intracavitary) Participants will be asked for informed consent to retrospectively and prospectively collect data on EVT.