Endoscopic removal of biliary self-expandable metallic stents: a prospective study.

Background and study aims: The transpapillary endoscopic insertion of self-expandable metallic stents (SEMSs) has been widely used for the palliation of unresectable malignant biliary obstruction. We attempted the endoscopic removal of malfunctioning SEMSs. The aim of this study was to assess the feasibility and safety of the endoscopic removal of SEMSs by comparing the results between removal of covered and uncovered SEMSs. Patients and methods: 30 patients with a malfunctioning biliary SEMS prospectively underwent an attempt at endoscopic removal of the biliary SEMS over a 2-year period. Removal of the malfunctioning SEMS was done with a therapeutic duodenoscope (ED-450XT5 or TJF-240), using a rat-tooth forceps. Of the 30 SEMS used, 22 were silicone-covered Wallstents, while eight were uncovered SEMSs including five uncovered Wallstents and three Zilver stents. The time for an attempt at each endoscopic removal was limited to 15 minutes in a single endoscopic procedure session. Results: The covered SEMSs were easily removed in 19 out of 22 patients (86.4%), whereas none of the eight uncovered SEMSs (0%) could be removed. The only factor predicting successful stent removal was the presence of a stent covering (P=0.000). There was no morbidity or mortality related to endoscopic removal of malfunctioning stents. Conclusions: In contrast to uncovered biliary SEMSs, in most cases malfunctioning covered biliary SEMSs can be easily and safely removed endoscopically using a rat-tooth forceps.