Updates in the endoscopic management of malignant biliary obstruction

Endoscopic biliary drainage is the mainstay treatment for malignant biliary obstruction. Biliary drainage is indicated for both inoperable patients and selected preoperative cases. Factors determining stent selection include resectability, the site of obstruction, the patient’s life expectancy, and cost-effectiveness. Generally, plastic stents are recommended for preoperative drainage, and self-expandable metallic stents (SEMS) are used for palliative drainage. However, SEMS has been shown to be a beneficial modality for preoperative drainage because of its long patency. For distal malignant obstruction, either uncovered or fully covered SMES can be used, whereas uncovered SEMS are suitable for hilar obstruction. If life expectancy is more than 3 months, SEMS are preferable over plastic stents to avoid reinterventions. Endoscopic retrograde cholangiopancreatography (ERCP) has been the primary method for endoscopic drainage. Endoscopic ultrasound-guided biliary drainage (EUS-BD) is an alternative modality when ERCP fails or is not possible. There are several methods to perform biliary drainage and stent placement through EUS guided, including hepaticogastrostomy, choledochoduodenostomy, and antegrade stent through trans-gastric access. EUS-BD has been shown to have more than 90% technical and clinical success and requires fewer unscheduled reinterventions when compared to the percutaneous approach. When compared to ERCP, EUS-BD with transmural stent placement eliminates the risk of postprocedural pancreatitis. However, EUS-BD is more challenging when the biliary system is not significantly dilated. Recently, a meta-analysis has shown that EUS-BD has comparable technical and clinical success as ERCP when used as a primary drainage method for malignant distal bile duct obstruction.
ERCP and EUS-BD have different advantages and drawbacks. EUS-BD is useful in patients with surgically altered anatomy and limited access to the major papilla. Therefore, the selection of drainage method should be based on the patient’s condition, anatomy, and endoscopist’s expertise. A strategic approach should be applied to help stratify suitable patients for the optimal drainage procedure.