Role of Endoscopy in Malignant Biliary Obstruction.

Malignant biliary obstruction (MBO) represents a critical clinical challenge characterized by bile duct compromise leading to severe complications, including intractable jaundice, recurrent cholangitis, biliary cirrhosis, and hepatic failure. Classification into distal MBO (DMBO) and hilar MBO (HMBO) guides therapeutic decision-making, with the former predominantly caused by pancreatic head adenocarcinoma and extrahepatic cholangiocarcinoma, while perihilar cholangiocarcinoma represents the principal etiology of the latter. The high morbidity and mortality associated with MBO necessitate prompt, expert intervention. While endoscopic retrograde cholangiopancreatography (ERCP) with transpapillary biliary drainage (TBD) has traditionally served as the cornerstone of management for unresectable tumors, endoscopic ultrasound (EUS)-guided biliary drainage has emerged as a compelling alternative, particularly when conventional ERCP proves technically unsuccessful or anatomically unfeasible. This review comprehensively examines current endoscopic strategies for MBO, emphasizing the complementary roles of ERCP and EUS-based techniques. Optimal outcomes require intervention by experienced endoscopists at high-volume tertiary centers, with individualized treatment selection based on anatomical considerations, tumor characteristics, patient factors, and local expertise.