Duodenal invasion is a risk factor for the early dysfunction of biliary metal stents in unresectable pancreatic cancer

Background: Although the placement of self-expandable metal stents (SEMSs) has been widely accepted as palliation for distal malignant biliary obstruction, the risk factors for their early dysfunction remain unclear. Objective: To identify risk factors for early (<3 months) SEMS dysfunction in unresectable pancreatic cancer. Design: A multicenter retrospective study. Setting: Five tertiary referral centers. Patients: Patients were included who underwent first-time SEMS placement for distal malignant biliary obstruction caused by pancreatic cancer between April 1994 and August 2010. Main Outcome Measurements: Rates and causes of early dysfunction were evaluated, and risk factors were analyzed. Results: In all, 317 eligible patients were identified. Covered SEMSs were placed in 82% of patients. Duodenal invasion was observed endoscopically in 37%. The median time to dysfunction was 170 days. The rates of all and early SEMS dysfunction were 55% and 31%, respectively. The major causes of SEMS dysfunction were food impaction and nonocclusion cholangitis (21% each) in early dysfunction and sludge (29%) in nonearly dysfunction. The rate of early dysfunction was 42% with duodenal invasion and 24% without duodenal invasion (P =.001). Early dysfunction caused by food impaction was more frequent in patients with duodenal invasion (10% and 4%, P =.053). Duodenal invasion was a risk factor (odds ratio 2.35; 95% CI, 1.433.90; P =.001) in a multiple logistic regression model. Limitations: A retrospective design. Conclusions: Duodenal invasion is a risk factor for early SEMS dysfunction in patients with pancreatic cancer.