['Controversy exists regarding whether to place a plastic or a metal endobiliary stent in patients with resectable pancreatic cancer who require biliary drainage. Although self-expandable metal stents (SEMS) provide better drainage compared with plastic stents, concerns remain that SEMS may compromise resection and increase postoperative complications. Our objective was to compare surgical outcomes of patients undergoing pancreaticoduodenectomy (PD) with SEMS in place vs. plastic endoscopic stents (PES) and no stents (NS).', 'We performed a retrospective analysis from a prospective database of all patients undergoing either attempted or successful PD with SEMS, PES, or NS in place at the time of operation. Patients were compared with regard to perioperative complications, margin status, and the rate of intraoperative determination of unresectability.', 'A total of 593 patients underwent attempted PD. Of these, 84 patients were locally unresectable intraoperatively and 509 underwent successful PD, of which 71 had SEMS, 149 had PES, and 289 had NS. Among patients who had a preoperative stent, SEMS did not increase overall or serious postoperative complications, 30-day mortality, length of stay, biliary anastomotic leak, or positive margin, but was associated with more wound infections and longer operative times. In those with adenocarcinoma, intraoperative determination of local unresectability was similar in the SEMS group compared with other groups, with 16 (19.3%) in SEMS compared with 29 (17.7%) in PES (P=0.862), and 31 (17.5%) in NS (P=0.732).'] Do biliary self-expandable metal stents adversely affect pancreaticoduodenectomy?