Refractory benign biliary strictures (BBS) often require prolonged endoscopic treatment with multiple plastic stents (MPS), leading to repeated ERCP sessions and a high procedural burden. Fully covered self-expandable metal stents (FCSEMS) have been introduced as an alternative, but the optimal strategy—initial versus rescue FCSEMS—remains unclear. This study aimed to compare clinical outcomes of different stent strategies and to identify risk factors for stricture recurrence in patients with refractory BBS.

In this multicenter retrospective cohort study, 150 patients with refractory BBS treated between 2016 and 2023 at four tertiary referral centers were analyzed. Patients were classified into three groups: plastic–plastic, plastic–metal (conversion to FCSEMS after plastic stents), and metal–metal (initial FCSEMS). Refractory BBS was defined as persistent stricture despite ≥12 months of plastic stenting or ≥6 months of FCSEMS. The primary outcome was stricture resolution; secondary outcomes included treatment duration, number of ERCP sessions, adverse events, and recurrence-free period. Predictors of recurrence were evaluated using multivariable logistic regression and ROC analysis.

Of the 150 patients, 32, 48, and 70 were assigned to the plastic–plastic, plastic–metal, and metal–metal groups, respectively. Initial FCSEMS significantly reduced treatment duration (297.8 vs. 581.4 and 600.7 days; p < 0.01) and the number of ERCP procedures (4.0 vs. 7.4 and 6.1; p < 0.001). Stricture resolution at 12 and 24 months was higher in the metal–metal group (80.0% and 92.9%) than in plastic-first strategies (37.5% and 73.8%; p < 0.001 and p = 0.002). Recurrence rates after stent removal were similar among groups (27.5–31.3%, p = 0.786). Early cholangitis, late cholangitis, and post-ERCP pancreatitis were significantly more frequent in the plastic–plastic group. Living donor liver transplantation (LDLT) (OR 4.13, p = 0.003) and stricture length ≥12 mm (OR 4.87, p < 0.001) were independent predictors of recurrence.

In refractory BBS, an initial FCSEMS strategy shortens treatment duration, reduces ERCP burden, and improves stricture resolution without increasing recurrence, while plastic stents are associated with higher infectious complication rates. LDLT and longer strictures identify patients at high risk of recurrence. Early consideration of FCSEMS may represent an efficient therapeutic approach and should be further validated in prospective trials.