Predictive Factors for Endoscopic Stenting Patency and Patient Survival in Unresectable Malignant Biliary Obstruction: A Cohort Study at a Tertiary Institution

Aim: Factors associated with the biliary stent dysfunction and long-term survival are not clearly established. To analyze factors associated with stent patency in palliative biliary drainage (BD) and to evaluate the factors associated with patient survival. Material and M ethods: Observational retrospective study with consecutive inclusion of patients with unresectable biliopancreatic tumours who underwent BD by ERCP between January-2015 and December-2016. To analyze the factors associated with patient survival, the hazard ratio obtained through a Cox model was used. The follow-up review period was limited up to January 2018 (from at least one year after the endoscopic procedure) or the patient´s death. Results: Forty-four patients were included during the study period. The clinical success rate of overall biliary stents was 93.2% and total AE rate was 18.2%. The basal biliary stent was functional in 79.5%; in the remaining cases, endoscopic reinterventions were necessary. The median time until the loss of stent patency was 131 days (Q1-Q3; 85-387days). None of the parameters analyzed were associated with stent dysfunction. The patients who required endoscopic reinterventions had a longer survival time (median of 422days [Q1-Q3; 281-520] vs 162days [Q1-Q3; 37-264], p=0.001). Oncological treatment, partially covered self-expandable metal stent, and high albumin were statistically associated with a longer survival. Conclusions: The majority of biliary stents were functional, without the need to repeat the ERCP sessions. The need for stent repermeabilization did not negatively influence patient survival.