Comparison of External and Internal Transanastomotic Pancreatic Duct Stents After Pancreaticoduodenectomy: A Propensity-Weighted Cohort Study

Purpose Postoperative pancreatic fistula (POPF) remains the most consequential complication after pancreaticoduodenectomy (PD), and the optimal transanastomotic pancreatic duct drainage strategy is still debated. We evaluated whether external versus internal transanastomotic pancreatic duct stenting is associated with clinically relevant POPF (CR-POPF) and early postoperative outcomes after PD. Methods We retrospectively analyzed consecutive open pancreatic resections performed for non-traumatic indications at Ankara University (İbni-Sina and Cebeci Hospitals) between 2010 and 2020. To ensure technical homogeneity, we included only patients who underwent PD reconstructed with a standardized end-to-side duct-to-mucosa pancreaticojejunostomy and who received a transanastomotic pancreatic duct stent (external or internal), had at least one peripancreatic closed-suction drain, and had postoperative day 3 drain amylase available. The final cohort comprised 302 patients (external n = 238; internal n = 64). The primary outcome was CR-POPF (ISGPS grade B–C); secondary outcomes included any-grade POPF, postoperative biliary leakage (POBL), and 30-day mortality. To mitigate confounding, we applied stabilized inverse probability of treatment weighting (IPTW) based on a prespecified propensity score model, followed by IPTW-weighted logistic regression. Results Any-grade POPF occurred in 18.9% and CR-POPF in 9.9% of patients; 30-day mortality was 3.6%. CR-POPF was lower with external versus internal stenting (8.0% vs 17.2%, p = 0.029), as was POBL (4.6% vs 14.1%, p = 0.019). In the IPTW analysis, external stenting was associated with reduced odds of CR-POPF (OR 0.31, 95% CI 0.14–0.70) and larger pancreatic duct diameter (OR 0.77, 95% CI 0.62–0.94) independently reduced CR-POPF risk. Thirty-day mortality was numerically lower with external stenting (2.5% vs 7.8%, p = 0.059). Conclusion In a standardized duct-to-mucosa PD cohort, external transanastomotic pancreatic duct stenting was associated with lower CR-POPF and fewer biliary leaks compared with internal stenting, with a descriptive trend toward lower early mortality.