500 - A Clinical Application Study on Biliary Stent-Based Comprehensive Interventional Therapy for Advanced Pancreatic Cancer with Obstructive Jaundice

Purpose: This study aims to investigate the impact of iodine-125 intraluminal brachytherapy on SPT and OS in patients with advanced pancreatic cancer complicated by obstructive jaundice, which may provide evidence for optimizing multimodal interventional strategies for patients with pancreatic cancer.

Materials and Methods: This retrospective study enrolled 262 patients with advanced pancreatic cancer complicated by obstructive jaundice who had underwent metallic biliary stent placement. Patients were stratified into the I-125 group (n=97) and the control group (n=165). A 1:1 PSM was performed using a caliper width of 0.2 standard deviations of the propensity score. The primary endpoints were SPT and OS. Survival curves were generated using the Kaplan-Meier method, with between-group differences assessed by log-rank test. Variables with p< 0.05 in univariate Cox regression were incorporated into multivariate Cox proportional hazards models to identify independent prognostic factors.

Results: At 1 month post biliary stent placement, significant reductions of serum bilirubin, transaminases, and CA19-9 levels compared to their pre-drainage values were observed in this study. The overall cohort demonstrated a median SPT of 7.63 months (95% CI 7.10-8.16), a stent restenosis rate of 36.2%, and a median OS of 9.40 months (95% CI 9.11-9.69). After 1:1 PSM (62 patients per group), the I-125 group showed a significantly longer median SPT (9.44 months vs. 6.21 months, p< 0.001) and lower restenosis rate (17.7% vs. 43.5%, p=0.002) compared to the stent-alone group. However, no significant OS difference was observed between groups (10.59 months vs. 9.07 months, p=0.248). Cox analysis suggested that intratumoral brachytherapy (HR 0.382, p< 0.001) was an independent protective factor for SPT; ECOG 2 score (HR 1.572, p=0.019) was an independent risk factor for SPT. The independent risk factors for OS included ECOG 2 score (HR 1.469, p=0.042) and post-stent CA19-9≥500 ku/L (HR 1.322, p=0.046).

Conclusion: Biliary stent combined with iodine-125 intraluminal brachytherapy significantly prolonged stent patency time compared to stent-alone in patients with advanced pancreatic cancer complicated by obstructive jaundice, although it did not significantly improve survival outcomes. Higher ECOG performance status at initial diagnosis and elevated CA19-9 levels after jaundice resolution were associated with poor prognosis.