Plastic vs. Covered Metal vs. Uncovered Metal Biliary Stents for the Management of Malignant Biliary Obstruction

Malignant biliary obstruction can result from extrinsic processes, such as proximal pancreatic ductal adenocarcinoma or metastatic lesions, or from intrinsic lesions such as cholangiocarcinoma. Malignant biliary obstruction is typically treated endoscopically with placement of either plastic (polyethylene) or metal biliary stents. Metal stents have a wider diameter than plastic stents, and have been shown to have higher patency rates, but are also 15-40 times the cost of plastic stents. Metal stents with a polymer coating have been developed to prevent tumor ingrowth into the stent, which can lead to stent occlusion. Cost analysis has demonstrated an advantage to the use of metal stents in patients with unresectable disease, or who may achieve operable status following neoadjuvant chemotherapy, while either plastic stents or metal stents are used when patients are deemed to have a surgically resectable lesion. Patient's determined to have resectable, or borderline resectable malignancy (those who may achieve resectability status following neoadjuvant chemotherapy) will receive either plastic, uncovered metal, or covered metal stents in a randomized fashion, while patients determined to have surgically unresectable malignancy will randomly receive either covered or uncovered metal biliary stents. The primary aim of this study is to prospectively evaluate stent occlusion rates in patients presenting with malignant biliary obstruction. Secondary aims of the study will include a cost analysis of each stent type, rate of hospital admission following stent placement, days off of chemotherapy due to procedural complication, and rate of acute cholecystitis associated with stent placement.

Inclusion criteria

• Male or female older than 18
• Capable of providing written informed consent
• Presenting with malignant biliary obstruction requiring biliary drainage either from proximal pancreatic malignancy, metastatic disease, or intrinsic biliary malignancy. The patient must have an established diagnosis of underlying malignancy, and surgical resectability status established, prior to enrollment in this study.

Exclusion criteria

• Inability to undergo conscious sedation or monitored anesthesia
• Prior pancreatico-biliary surgery
• Evidence of acute cholecystitis at time of endoscopic procedure
• Intraluminal filling defect requiring endoscopic removal prior to stent placement
• Inability to provide written informed consent
• Malignancy not verified prior to stent placement