Abstract
<jats:p>Pancreatitis is a well-recognized complication of ~10% of ERCP procedures and 1-3% of EUS-guided pancreatic tissue acquisitions (TA). The first part of this thesis focuses on reducing this risk. Prevention of post-ERCP pancreatitis (PEP) starts with careful patient selection. In patients with an intermediate or high likelihood of common bile duct stones, EUS prior to ERCP could prevent unnecessary procedures. Rectal diclofenac before ERCP is standard prophylaxis against PEP. Interestingly, patients who do not develop PEP more frequently exhibit slower diclofenac metabolism, suggesting that rapid metabolism may reduce its protective effect. Ongoing research is investigating whether this results in lower diclofenac plasma concentrations. Given the comparable pathophysiology of post-ERCP and post-EUS pancreatitis, rectal diclofenac is also recommended before EUS-TA. The FLUYT-2 study demonstrated that immediate placement of a prophylactic pancreatic duct stent after unintentional pancreatic duct cannulation during ERCP significantly reduces the risk of PEP. The second part focuses on improving endoscopic management of pancreatic cancer. A newly developed asymmetric three-prong fine-needle biopsy (FNB) needle enables high diagnostic accuracy with only two needle passes. After failed ERCP for distal malignant biliary obstruction, EUS-guided biliary drainage offers an effective alternative to percutaneous drainage, with fewer adverse events and preserved surgical options. Finally, contrast-enhanced EUS was explored as a minimally invasive tool to predict chemotherapy response in pancreatic cancer, supporting personalized treatment strategies.</jats:p>