Endoscopic biliary stenting for malignant hilar biliary, obstructions

Endoscopic biliary stenting (EBS) is a well-established palliative treatment and the first choice for the management of unresectable malignant hilar biliary obstructions. Plastic tube stents (PSs) and self-expandable metallic stents (SEMSs) are the most commonly used in EBS. The efficacy of SEMSs has been extensively described for the treatment of distal biliary obstructions ; however, their efficacy has not been sufficiently evaluated for the treatment of unresectable malignant hilar biliary obstructions. Therefore, the more effective stent type and mode of stenting (unilateral versus bilateral) for unresectable malignant hilar biliary obstructions remain controversial. EBS plays an important role in maintaining the patient's condition and in determining the subsequent prognosis and quality of life, and therefore, it is essential that biliary stents do not result in occlusions or complications during the period of clinical use. In this regard, SEMSs are more suitable for unresectable malignant hilar biliary obstructions. In general practice, we first perform endoscopic naso-biliary drainage (ENBD) followed by additional ENBD tube placement in cases where unilateral drainage is not sufficient. A single stent is used for unilateral drainage and 2 stents are used for bilateral drainage after improving jaundice and cholangitis. SEMSs also help reduce the number of re-intervention sessions required and the overall treatment cost compared to PSs. Furthermore, SEMSs with low axial force are important for long-term patency and decreasing the incidence of SEMS-associated complications, as these SEMSs confer good conformability, enabling a close fit with the bile duct. Finally, SEMSs with a large cell width make the initial partial stent-in-stent placement and re-intervention easier, safer, and more effective for unresectable malignant hilar biliary obstructions.