Management of benign biliary strictures with a novel retrievable self-expandable metal stent

Antimigration versus conventional fully covered metal stents in the endoscopic treatment of anastomotic biliary strictures after deceased-donor liver transplantation

INTRODUCTION

Migration of fully covered metal stents (FCMS) remains a limitation of the endoscopic treatment of anastomotic biliary strictures (ABS) following orthotopic liver transplantation (OLT). The use of antimigration FCMS (A-FCMS) might enhance endoscopic treatment outcomes for ABS.

METHODS

Single center retrospective study. Consecutive patients with ABS following OLT who underwent ERCP with FCMS placement between January 2005 and December 2020 were eligible. Subjects were grouped into conventional-FCMS (C-FCMS) and A-FCMS. The primary outcome was stent migration rates. Secondary outcomes were stricture resolution, adverse event, and recurrence rates.

RESULTS

A total of 102 (40 C-FCMS; 62 A-FCMS) patients were included. Stent migration was identified at the first revision in 24 C-FCMS patients (63.2%) and in 21 A-FCMS patients (36.2%) (p = 0.01). The overall migration rate, including the first and subsequent endoscopic revisions, was 65.8% in C-FCMS and 37.3% in A-FCMS (p = 0.006). The stricture resolution rate at the first endoscopic revision was similar in both groups (60.0 vs 61.3%, p = 0.87). Final stricture resolution was achieved in 95 patients (93.1%), with no difference across groups (92.5 vs 93.5%; p = 0.84). Adverse events were identified in 13 patients (12.1%) with no difference across groups. At a median follow-up of 52 (IQR: 19-85.5) months after stricture resolution, 25 patients (24.5%) developed recurrences, with no difference across groups (C-FCMS 30% vs A-FCMS 21%; p = 0.28).

CONCLUSIONS

The use of A-FCMS during ERCP for ABS following OLT results in significantly lower stent migration rates compared to C-FCMS. However, the clinical benefit of reduced stent migration is unclear. Larger studies focusing on stricture resolution and recurrence rates are needed.

Migration rate using fully covered metal stent in anastomotic strictures after liver transplantation: Results from the BASALT study group

BACKGROUND AND STUDY AIM

The traditional endoscopic therapy of anastomotic strictures (AS) after orthotopic liver transplantation (OLT) is multiple ERCPs with the insertion of an increasing number of plastic stents side-by-side. Fully covered self-expanding metal stents (cSEMS) could be a valuable option to decrease the number of procedures needed or non-responders to plastic stents. This study aims to retrospectively analyse the results of AS endoscopic treatment by cSEMS and to identify any factors associated with its success.

PATIENTS AND METHODS

Ninety-one patients (mean age 55.9 ± 7.6 SD; 73 males) from nine Italian transplantation centres, had a cSEMS positioned for post-OLT-AS between 2007 and 2017. Forty-nine (54%) patients were treated with cSEMS as a second-line treatment.

RESULTS

All the procedures were successfully performed without immediate complications. After ERCP, adverse events occurred in 11% of cases (2 moderate pancreatitis and 8 cholangitis). In 49 patients (54%), cSEMSs migrated. After cSEMS removal, 46 patients (51%) needed further endoscopic (45 patients) or radiological (1 patient) treatments to solve the AS. Lastly, seven patients underwent surgery. Multivariable stepwise logistic regression showed that cSEMS migration was the only factor associated with further treatments (OR 2.6, 95% CI 1.0-6.6; p value 0.03); cSEMS implantation before 12 months from OLT was associated with stent migration (OR 5.2, 95% CI 1.7-16.0; p value 0.004).

CONCLUSIONS

cSEMS appears to be a safe tool to treat AS. cSEMS migration is the main limitation to its routinary implantation and needs to be prevented, probably with the use of new generation anti-migration stents.

Intraductal placement of non-flared fully covered metallic stent for refractory anastomotic biliary strictures after living donor liver transplantation: Long-term results of prospective multicenter trial

BACKGROUND AND AIM

Fully covered self-expandable metallic stent (FCSEMS) may be an effective modality for managing anastomotic biliary stricture (ABS) after liver transplantation. However, stent migration and stent-induced ductal injury are the main limitations. The objective of this study was to evaluate the usefulness of an unflared, intraductal FCSEMS that was designed to minimize migration and ductal injury for refractory ABS after living donor liver transplantation (LDLT).

METHODS

A total of 32 consecutive patients with symptomatic ABS after LDLT unresolved by plastic stents with or without balloon dilation at four tertiary medical centers were prospectively enrolled. A short (3 or 5 cm) FCSEMS having long lasso (10 cm) used in this study had unflared convex ends to minimize tissue hyperplasia and smaller center portion to prevent migration. The FCSEMS was placed above the papilla and removed at 3-4 months after stenting.

RESULTS

Technical and clinical success rates of intraductal placement with FCSEMS were 100% (32/32) and 81.2% (26/32), respectively. Early stent migration was observed in five (15.6%) patients. However, three patients with early stent migration had stricture resolution without needing additional intervention. Intended stent removal was successful in 27 (100%) patients (median, 101 days; range, 23-118 days). No stent-induced ductal change was observed in all patients. Stricture recurrence was observed in 11.5% (3/26) of patients during 639 days of median duration of follow-up (range, 366-2079 days).

CONCLUSIONS

Intraductal placement of an unflared short FCSEMS may be a promising option for refractory ABS after LDLT with minimal stent-induced ductal injury and stent migration.

Drug-eluting fully covered self-expanding metal stent for dissolution of bile duct stones in vitro

BACKGROUND

The treatment of difficult common bile duct stones (CBDS) remains a big challenge around the world. Biliary stenting is a widely accepted rescue method in patients with failed stone extraction under endoscopic retrograde cholangiopancreatography. Fully covered self-expanding metal stent (FCSEMS) has gained increasing attention in the management of difficult CBDS.

AIM

To manufacture a drug-eluting FCSEMS, which can achieve controlled release of stone-dissolving agents and speed up the dissolution of CBDS.

METHODS

Customized covered nitinol stents were adopted. Sodium cholate (SC) and disodium ethylene diamine tetraacetic acid (EDTA disodium, EDTA for short) were used as stone-dissolving agents. Three different types of drug-eluting stents were manufactured by dip coating (Stent I), coaxial electrospinning (Stent II), and dip coating combined with electrospinning (Stent III), respectively. The drug-release behavior and stone-dissolving efficacy of these stents were evaluated in vitro to sort out the best manufacturing method. And the selected stone-dissolving stents were further put into porcine CBD to evaluate their biosecurity.

RESULTS

Stent I and Stent II had obvious burst release of drugs in the first 5 d while Stent III presented controlled and sustainable drug release for 30 d. In still buffer, the final stone mass-loss rate of each group was 5.19% ± 0.69% for naked FCSEMS, 20.37% ± 2.13% for Stent I, 24.57% ± 1.45% for Stent II, and 33.72% ± 0.67% for Stent III. In flowing bile, the final stone mass-loss rate of each group was 5.87% ± 0.25% for naked FCSEMS, 6.36% ± 0.48% for Stent I, 6.38% ± 0.37% for Stent II, and 8.15% ± 0.27% for Stent III. Stent III caused the most stone mass-loss no matter in still buffer or in flowing bile, which was significantly higher than those of other groups (P < 0.05). In vivo, Stent III made no difference from naked FCSEMS in serological analysis (P > 0.05) and histopathological examination (P > 0.05).

CONCLUSION

The novel SC and EDTA-eluting FCSEMS is efficient in diminishing CBDS in vitro. When conventional endoscopic techniques fail to remove difficult CBDS, SC and EDTA-eluting FCSEMS implantation may be considered a promising alternative.

Endoscopic treatment of anastomotic biliary stricture after adult deceased donor liver transplantation with multiple plastic stents versus self-expandable metal stents: a systematic review and meta-analysis

Anastomotic biliary strictures (ABSs) occur in up to 15% of patients after liver transplantation (LT). The aim of this study was to compare the efficacy and safety of self-expandable metal stents (SEMS) versus multiple plastic stents (MPS). Databases were searched through April 2017. The outcome measures were technical success, stricture resolution, recurrence and complications. We synthesized the findings descriptively and performed a meta-analysis. Three randomized controlled trials and one retrospective cohort study were identified, including 179 MPS and 119 SEMS patients. Outcome data were pooled in a meta-analysis that showed an advantage of SEMS in terms of the number of ERCP procedures (mean difference: 1.69 ERCP; 95% CI, 1-2.39; P < 0.00001) and treatment days (mean difference: 40.2 days; 95% CI, 3.9-76.4; P = 0.03), with no differences in terms of ABS resolution or recurrence. Fourteen case series reported MPS outcomes and fifteen reported SEMS outcomes, including 647 and 419 patients, respectively. Based on low-quality evidence, we cannot draw any reliable conclusions on the superiority of MPS or SEMS strategies. Even though shorter treatment times and fewer ERCP procedures support the use of SEMS, whether one technique has well-defined advantages over the other remains unclear.

Clinical outcome of endoscopic covered metal stenting for resolution of benign biliary stricture: Systematic review and meta-analysis

BACKGROUND AND AIM

Management of benign biliary stricture is challenging. Endoscopic therapy has evolved as the first-line treatment for various benign biliary strictures. However, covered self-expandable metal stents (CSEMS) have not been approved by the United States Food and Drug Administration for the treatment of benign biliary stricture. With this goal, we conducted the present systemic review and meta-analysis to evaluate the efficacy and safety of endoscopic stenting with CSEMS in the treatment of benign biliary stricture.

METHODS

Systematic review and meta-analysis by searching PubMed, MEDLINE and Embase databases.

RESULTS

In total, 37 studies (1677 patients) fulfilled the inclusion criteria. Pooled stricture resolutions were achieved in 83% of cases. Median stent dwelling time was 4.4 months, with median endoscopic retrograde cholangiopancreatography sessions of 2.0. Stricture recurrence at 4-year follow up was 11% (95% CI, 8-14%). Pooled complication rate was 23% (95% CI, 20-26%).

CONCLUSIONS

Placement of CSEMS is effective in the treatment of benign biliary stricture with relatively short stenting duration and low long-term stricture recurrence rate. However, more prospectively randomized studies are required to confirm the results.

Covered metal stents in endoscopic therapy of biliary complications after liver transplantation

There is growing interest in using covered self-expandable metal stents for the treatment of benign biliary conditions, and the presence of anastomotic biliary strictures and leaks after liver transplantation provide a valuable opportunity for testing them. The performance of the stents is encouraging, and the technical success rate is high. They provide larger diameter dilation and are easily removed, and can potentially limit costs by reducing the number of procedures needed to treat anastomotic biliary strictures. However, drawbacks such as sub-optimal tolerability and migration may affect both patient management and costs. New stent designs are currently being evaluated. Randomized controlled trials and cost-effectiveness analyses comparing covered metal stents with multiple plastic stent endotherapy are warranted in order to define the role of the former as first-line or rescue treatment.

Novel biliary self-expanding metal stents: indications and applications

Endoscopic insertion of a self-expanding metal stent (SEMS) through a malignant common bile duct stricture is the first line of palliation for malignant jaundice. Patency of these stents remains a major concern. SEMS dysfunction can result from tumor ingrowth, overgrowth and/or clogging. Initial SEMS modifications involved covering the central part of the stent in order to reduce ingrowth and ultimately increase patency. Fully covered stents became available shortly after reports of their use in human patients. The potential removability and radial strength of SEMS have led to evaluation of their use in new indications including benign biliary strictures, post sphincterotomy bleeding and perforation. Other aspects of development include the addition of features such as anti-reflux valves, drug elution and spontaneous biodegradability. These aspects and their clinical implications are reviewed and discussed.