Metal biliary stent transection with over-the-scope clip removal system. We have no disclosures. Since the late 1980s, uncovered and covered self-expanding biliary stents have been used to address biliary obstruction. Given their efficacy, they've been used for biliary decompression in pancreatic and biliary cancers. While fully covered stents can be removed easily most of the time, uncovered stents cannot be removed once tissue ingrowth occurs. With improvements in cancer treatments, these patients are living longer than the intended lifespan of these devices, thus requiring more endoscopic procedures and interventions. Several published cases have shown utility of argon plasma coagulation, or APC, in modifying uncovered stents. However, the technique is time-consuming and carries a risk of adjacent tissue injury. We describe two cases of distorted metal stents requiring modification and transection using a system designed for over-the-scope clip removal. This is a bipolar electrosurgical device that conducts thermal energy precisely between three prongs, limiting thermal injury to surrounding tissues. It allows for precise application of electrical energy to alter stents to the endoscopist liking. Our first case involves a 67-year-old gentleman with cholangiocarcinoma who had a fully covered metal stent placed in an outside facility for biliary decompression. He presented to our hospital where ERCP was planned for better evaluation of his anatomy and determined potential surgical receptability. Upon insertion of the duodenoscope into the second portion of the duodenum, an occluded and significantly migrated fully covered stent was identified. Following balloon clearance of debris, cholangiogram demonstrated that the stent was short of the perihilar obstruction. Attempts were made to remove the stent, but traction caused the distal wires of the stent to fray and ultimately cause the prosthesis to become distorted. Decision was made to trim the stent in order to prevent erosion into the duodenum and facilitate further attempts at biliary decompression. The OTSC removal system was used to fragment the individual wires along the circumference of the stent. The precision of electrothermal application allowed for systematic transection and minimal collateral damage to surrounding tissues. Once completely transected, the distal portion of the stent was able to be removed in one contiguous piece. Attention was returned to the biliary tree where a new fully covered biliary stent could be placed through the existing stent. This allowed for eventual placement of a 7 French by 12 centimeter plastic stent traversing the malignant obstruction. Our second case involves an 80-year-old gentleman with pancreatic cancer and biliary strictures who required an uncovered metal stent for biliary decompression. This stent was subsequently obstructed due to tumor ingrowth and a fully covered stent was placed to address rising bilirubin levels. At follow-up endoscopy, the fully covered stent had migrated distally and caused the duodenal ulceration. Attempts at stent removal were unsuccessful and ultimately caused the wires of the underlying uncovered stent to become frayed. As was done in the first case, an OTSC removal system was used to systematically fracture the wires of the uncovered stent. This allowed the fully covered stent to be successfully removed and for a new fully covered stent to be replaced within the lumen of the ingrown uncovered stent. Utilization of an OTSC removal system in cases where metal stents need to be modified or transected has the potential for shorter, more efficient procedures due to ease of use as compared to APC. It is a familiar device that has the benefits of precision and theoretically less collateral damage as compared to APC. These two cases demonstrate that an OTSC removal system is a safe and effective alternative to APC with regards to transecting and shortening metal stents that cannot be removed from the bile ducts. This device is often stocked in interventional endoscopy units and is promising as an off-label device for the modification of metal biliary stents.

OTSC system

biliary stents

tissue ingrowth

electrosurgical tool

endoscopic management