A multi-center retrospective study to systematically investigate the risk of pancreatitis caused by the placement of a fully covered metal stent across the duodenal papilla and its influencing factors

The latest research result led by the endoscopic team of Oriental Hepatobiliary Surgical Hospital has been published recently online in the internationally well-known Journal of Gastroenterology and Hepatology, titled " Influence of fully covered metal stenting on the risk of post-endoscopic retrograde cholangiopancreatography pancreatitis: A large multicenter study "

Fully covered metal stents (FCSEMS) are increasingly widely used in clinical treatment of benign and malignant biliary diseases. However, whether endoscopic placement of FCSEMS across duodenal papilla is associated with an increased risk of pancreatitis (PEP) after ERCP has been controversial since a long period. Therefore, this study aimed to explore the risk of PEP in patients receiving FCSEMS implantation.

This is a multi-center retrospective study involving five well-known endoscopic centers in China. They are Changhai Road Hospital of Oriental Hepatobiliary Surgical Hospital, Anting Hospital of Oriental Hepatobiliary Surgical Hospital, Affiliated Hangzhou First People's Hospital, Shandong Provincial Third Hospital, and Changhai Hospital. Totally 602 patients received endoscopic FCSEMS implantation during 2011-2018. Patients younger than 18 years or patients with a fully covered metal stent located above the duodenal papilla were not included.

The present study mainly observed the incidence of PEP and its risk factors.

Result:

PEP occurred in 56 cases (9.3%), among which 8 cases (1.3%) had moderate to severe PEP. The incidence of PEP was 14.6% (51/349) in the cases without pancreatic duct ectasis. The incidence of PEP was 18.6% if preventive measures were not taken. In the effect of PEP preventive measures, stent pre-implantation was more effective in reducing the incidence of PEP than rectal application of indomethacin suppository (3.5% vs. 10.8%, P=0.023). Multivariate logistic regression showed that difficult intubation (OR 2.837, 95%CI 1.245-6.465, P=0.013), pancreatic duct ectasis (OR 0.145, 95%CI 0.05-0.422, P<0.001) and pancreatic duct stent implantation (OR 0.247, 95%CI 0.089-0.686, P=0.007) were significantly related with PEP risks. In addition, the incidence of cholecystitis after covered metal stent implantation was 4.0%.

Figure 1 a patient with benign biliary stricture is placed with a fully covered metal stent and a plastic pancreatic duct stent through the duodenal papilla.

Figure. 2 Incidence of PEP after endoscope placement of fully covered metal stents.

This study is the largest multi-center study with the largest sample volume as far as we know, and the first study to systematically investigate the risk of pancreatitis caused by the placement of a fully covered metal stent across the duodenal papilla and its influencing factors. The results show that the overall risk of postoperative pancreatitis is slightly increased, especially in patients without pancreatic duct ectasis. Therefore routine preventive placement of pancreatic stents is recommended in this circumstance. The results of this study will be helpful to guide the clinical application of fully covered metal biliary stent.