Influence of fully covered metal stenting on the risk of post-endoscopic retrograde cholangiopancreatography pancreatitis: A large multicenter study·.

BACKGROUND AND AIM: Fully covered self-expandable metal stents (FCSEMSs) have been increasingly used in the management of benign or malignant biliary disorders. However, the risk of post-endoscopic retrograde cholangiopancreatography pancreatitis (PEP) with transpapillary placement of the FCSEMS remains controversial. This study therefore aimed to investigate the risk of PEP in patients who received FCSEMS implantation.

METHODS: In total, 602 patients who underwent endoscopic transpapillary FCSEMS placement at five Chinese medical centers, between 2011 and 2018, were included in this retrospective study. Patients who were younger than 18 years and with stent placement above the papilla were excluded from the study. PEP and the risk factors were reviewed.

RESULTS: PEP occurred in 56 (9.3%) patients, and eight (1.3%) of them experienced moderate-to-severe PEP. The incidence of PEP rose to 14.6% (51/349) when patients had no pancreatic duct (PD) dilation, and even to 18.6% if no prophylactic approaches were adopted. Prophylactic PD stenting showed better efficacy in reducing the incidence of PEP than did rectal use of indomethacin (3.5% vs 10.8%, P = 0.023). Multivariate logistic regression revealed that difficult cannulation (OR 2.837, 95% CI 1.245-6.465, P = 0.013), PD dilation (OR 0.145, 95% CI 0.05-0.422, P < 0.001), and PD stenting (OR 0.247, 95% CI 0.089-0.686, P = 0.007) were significantly associated with PEP risk. Post-procedure cholecystitis was found in 4.0% of patients.

CONCLUSION: The risk of post-procedure pancreatitis is modestly increased in patients receiving transpapillary FCSEMS placement, particularly when there is absence of PD dilation. Thus, prophylactic pancreatic stenting is recommended in such a condition.