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.