Risk factors for failure of endoscopic stenting of biliary strictures in chronic pancreatitis: a prospective follow-up study

OBJECTIVES: The aims of this study were to investigate the value of interventional endoscopy in patients with strictures of the common bile duct (CBD) caused by chronic pancreatitis (CP), and to define the subset of patients who may be at risk for failure of endoscopic intervention, in a prospective follow-up study. METHODS: A total of 61 patients with symptomatic CBD strictures caused by alcoholic CP were treated by endoscopic stent insertion for 1 yr with scheduled stent changes every 3 months. After the treatment period, all patients entered a follow-up program. RESULTS: Initial endoscopic drainage was successful in all cases, with complete resolution of obstructive jaundice. After 1 yr from the initial stent insertion, in 19 patients (31.1%) the obstruction was resolved, and stents were removed without any need of additional procedures. During a median follow-up of 40 months (range 18-66 months), 16 patients had no recurrence of symptomatic CBD stricture (long term success rate 26.2%). Of 45 patients who needed definitive therapy, 12 patients (19.7%) were treated with repeated plastic stent insertion and three (4.9%) with insertion of a metal stent, and 30 patients (49.2%) underwent surgery. Among the variables tested, calcification of the pancreatic head was the only factor that was found to be of prognostic value. Of 39 patients with calcification of the pancreatic head, only three (7.7%) were successfully treated by a 1-yr period of plastic stent therapy, whereas in 13 of 22 patients (59.1%) without calcification, this treatment was successful (p<0.001). CONCLUSIONS: Endoscopic drainage of biliary obstruction provides excellent short term but only moderate long term results. Patients without calcifications of the pancreatic head benefit from biliary stenting. Patients with calcifications were identified to have a 17-fold (95% CI=4-74) increased risk of failure of a 12 month course of endoscopic stenting.