Long-term outcomes of covered self-expandable metal stents for treating benign biliary strictures

Background and study aim: Fully covered, self-expandable metal stents (FCSEMSs) are acceptable tools for treating benign biliary stricture (BBS). However, little is known about the long-term outcomes of this technique. The aim of the present study was to evaluate the procedural and long-term outcomes of FCSEMSs for treating BBSs. Patients and methods: A total of 134 consecutive patients (median age 56 years; range 21-83) with BBS were retrospectively reviewed. The main outcomes were technical and clinical success, stricture resolution, recurrence, and adverse events. Outcomes were analyzed by reviewing patient medical records. Results: The success rates of FCSEMS placement and removal were 99.3% and 98.2%, respectively. Stricture resolution occurred in 103/132 (78.0%) of the patients (median stent duration, 93 days; range 1-489). The associated factors for stricture resolution were longer stent indwelling period (>= 120 days) and absence of stent migration. Stricture recurrence was seen in 26/103 patients (25.2%; 95% confidence interval [CI] 0.17-0.34) within a median of 390 days (range 4-903 days). Chronic pancreatitis was associated with stricture recurrence (hazard ratio [HR] 2.59, 95%CI 1.20-5.61; P = 0.02). Stent migration occurred in 41/132 patients (31.1%; 95%CI 0.23-0.39). The FCSEMS with anchoring flaps appeared to protect against stent migration (HR 0.22, 95%CI 0.08-0.63; P<0.01). Conclusion: FCSEMSs had a high success rate for BBS resolution. Longer indwelling periods and the absence of stent migration might be important factors for stricture resolution.