Introduction

Endoscopic retrograde cholangiopancreatography (ERCP) with self-expandable metal stent (SEMS) placement has become the treatment of choice for biliary drainage in patients with distal malignant biliary obstruction. However, biliary SEMS placement is associated with an increased incidence of post-ERCP pancreatitis (PEP). Although previous studies reported conflicting results, endoscopic sphincterotomy (ES) may reduce the risk of this potentially serious complication by alleviating pancreatic duct pressure. In this study, we evaluated whether ES was superior in reducing PEP after SEMS placement in patients with malignant biliary obstruction.

Aims & Methods

This multicenter, randomized, controlled trial was conducted in 19 hospitals. We included all consecutive patients with suspected malignant biliary obstruction in need for biliary drainage. Patients were randomized during ERCP to receive either endoscopic sphincterotomy (ES group) or no endoscopic sphincterotomy (control group) prior to fully covered SEMS placement. Patients were blinded to treatment allocation. The primary endpoint was PEP within 30 days. Secondary endpoints included pancreatitis severity grade, 30-day mortality, and other procedure-related severe adverse events (i.e. gastrointestinal bleeding, perforation, cholangitis, and cholecystitis) within 30 days. An interim analysis was performed after 50% of patients (n=259) had completed follow-up.

Results

Between May 2015 and March 2022, a total of 259 patients were randomized, with 125 patients (48%) in the ES group and 134 (52%) patients in the control group. Overall, 141 patients (54%) were male and the mean age was 69 (SD±10) years. Most patients were diagnosed with pancreatic cancer (72% in the ES group vs. 76% in the control group, Table 1).
PEP occurred in 23 patients (17%) in the ES group and in 26 patients (21%) in the control group (relative risk [RR] 0.83, 95% confidence interval [CI] 0.50 – 1.37, P=0.46, Table 1). In both groups, most patients experienced mild pancreatitis (83% vs. 81%, respectively). No cases of gastrointestinal bleeding or perforation were observed. Cholangitis (2% vs. 2%) and cholecystitis (6% vs. 6%) rates were similar between groups.

Table 1. Baseline characteristics and outcomes in patients undergoing endoscopic sphincterotomy (ES) or no sphincterotomy

Conclusion

This multicenter, randomized, controlled trial found no difference in PEP between patients with and without endoscopic sphincterotomy prior to fully covered SEMS placement. Therefore, we could not prove superiority of an endoscopic sphincterotomy to prevent PEP in this specific setting.