Covered Self-expandable Metal Stent, 6 Versus 12 Months, for Benign Biliary Stricture Caused by Chronic Pancreatitis: a Prospective Randomized Study

All consecutive patients admitted for ERCP and treated for benign biliary stricture caused by chronic pancreatitis with or without acute pancreatitis are prospectively enrolled in the study. The age and gender of the patients and the aetiology of the pancreatitis will be recorded.

At initial presentation, clinical and laboratory findings recorded include liver function tests, abdominal pain, jaundice and cholangitis. Pancreatic calcifications are documented in abdominal computed tomography. Patients with malignancies, cirrhosis, acute/chronic hepatitis or abnormal hepatic imaging studies are excluded. Patients with first attack of acute pancreatitis will be excluded.

The approval of the ethics committee of the hospital has been obtained. An informed consent will be obtained from all patients.

All patients are prepared and sedated for ERCP as per standard medical practice of the hospital. At the initial ERCP, an endoscopic sphincterotomy will be performed and the presence/absence of bile duct stones above the stricture and the treatment of stones are recorded. A pancreatic stent will be inserted if indicated. For the initial ERCP the patients will be randomized into two groups: those who receive 10 mm diameter cSEMS and those who receive 12 mm diameter cSEMS into the bile duct. For the randomization, sealed envelopes will be used. The length of the cSEMS is recorded.

Further ERCP for stent removal will be performed after six months for the patients with 12 mm diameter cSEMS and after twelve months for the patients with 10 mm diameter cSEMS. In case of stent migration during the follow-up, the stent will be replaced by a similar new cSEMS. If a pancreatic stent will be placed, the removal or replacement will be handled according to the hospital practice.