A Prospective Multicenter Study of “Inside Stents” for Biliary Stricture: Multicenter Evolving Inside Stent Registry (MEISteR)

Abstract

Background: Endoscopic biliary stent placement is the standard of care for biliary strictures, but stents across the papilla are prone to duodenobiliary reflux, which can cause stent occlusion. Preliminary studies of “inside stents” placed above the papilla showed encouraging outcomes, but prospective data with a large cohort were not reported. Methods: This was a prospective multicenter registry of commercially available inside stents for benign and malignant biliary strictures. Primary endpoint was recurrent biliary obstruction (RBO). Secondary endpoints were technical success of stent placement and removal, adverse events, and stricture resolution. Results: A total of 209 inside stents were placed in 132 (51 benign and 81 malignant) cases with biliary strictures in 10 Japanese centers. During the follow-up period of 8.4 months, RBO was observed in 19% of benign strictures. The RBO rate was 49% in malignant strictures, with the median time to RBO of 4.7 months. Technical success rates of stent placement and removal were both 100%. The adverse event rate was 8%. Conclusion: This prospective multicenter study demonstrated that inside stents above the papilla were feasible in malignant and benign biliary strictures, but a randomized controlled trial is warranted to confirm its superiority to conventional stents across the papilla.

Self‐expandable metal stents have longer patency and less cholangitis than inside stents in malignant perihilar biliary obstruction

“…[7][8][9][10]13,14 In addition, a multicenter prospective study showed that TRBO for malignant biliary stricture was 4.7 months. 15 Thus, our results regarding TRBO in the IS group were comparable with those of most previous studies. However, the reason why the median TRBO with ISs (113 days, or 3.7 months) in this study was slightly shorter than the results of a previous prospective study (4.7 months) might be explained by aggressive IS exchange when cholangitis occurred, even in patients who had non-occlusion cholangitis without obvious jaundice (total bilirubin < 2.0 mg/dl).…”

“…Previous studies had found that IS patency in malignant biliary obstruction ranged from 85.2 to 190 days 7–10,13,14 . In addition, a multicenter prospective study showed that TRBO for malignant biliary stricture was 4.7 months 15 . Thus, our results regarding TRBO in the IS group were comparable with those of most previous studies.…”

Pancreato‐biliary endoscopy: History of endoscopic biliary drainage

“…A slim-covered SEMS (6 mm diameter) and a stent placed above the papilla show promise for unresectable hilar MBO because of their long TRBO and exchangeability (Figs 2,3). 18 MANAGEMENT OF BENIGN BILIARY STRICTURE B ENIGN BILIARY STRICTURE (BBS) can be treated with CSEMS instead of PS. CSEMS placement for BBS was first reported in Japan in 2003 by Enya et al, 19 who used the polyurethane-covered Strecker stent and Diamond stent.…”

“…A slim‐covered SEMS (6 mm diameter) and a stent placed above the papilla show promise for unresectable hilar MBO because of their long TRBO and exchangeability (Figs 2,3). 18 …”

Recent Advances in Pancreato-Biliary Endoscopic Intervention: How to Resolve Unmet Needs in Pancreato-Biliary Diseases Endoscopically

“…This stent was developed by a Japanese endoscopist [12][13][14] but has not been evaluated prospectively or in a comparative study. A prospective single-arm multicenter study evaluated the feasibility of an inside stent [15]. The inside stent showed a long time to RBO in cases of benign biliary stricture (BBS) and superiority to conventional plastic stents in malignant cases.…”