Risk factors for post-endoscopic retrograde pancreatography pancreatitis in malignant extrahepatic biliary obstruction: a retrospective single-center study

Abstract

Background. Decompression interventions under the endoscopic retrograde cholangiopancreatography (ERCP) is the method of choice in malignant extrahepatic biliary obstruction (MEHBO). Acute pancreatitis is the most common complication of ERCP. Many studies have been performed to identify the risk factors for post-ERCP pancreatitis (PEP). However, these works in general include the analysis of ERCP in patients with various causes of biliary obstruction without subdividing patients with malignant obstruction. Purpose.The aim of this study was to determine the risk factors for PEP in patients with MEHBO. Materials and Methods. A retrospective analysis of 100 cases of ERCP in MEHBO was done. PEP was in 2 patients, and 14 patients had hyperamylasemia (HA). The following factors were analyzed: gender, age, level of MEHBO, obstruction of the main pancreatic duct (MPD), total bilirubin level, history of endoscopic papillosphincterotomy (EPST), periampullary diverticulum, successful ERCP, primary selective biliary cannulation, catheterization and/or contrast injection into MPD, Precut EPST, successful decompression. Results and discussion. Univariate analysis showed that PEP is associated with an obstruction at the level of the proximal and middle third of the hepaticocholedochus (p = 0.004) and with absence of MPD obstruction (p = 0.022); female gender (p = 0.012), obstruction at the level of the proximal and middle third of the hepaticocholedochus (p < 0.001), absence of MPD obstruction (p < 0.001), catheterization and/or contrast injection into MPD (p = 0.040) are associated with PEP or hyperamylasemia (HA); female gender (p = 0.024), obstruction at the level of the proximal and middle third of the hepaticocholedochus (p < 0.001), absence of MPD obstruction (p=0.006), catheterization and/or contrast injection into MPD (p = 0.035), successful decompression (p = 0.004) are associated with HA. Multivariate regression analysis showed that, for PEP and for PEP or HA as well as for HA, the risk factors are obstruction at the level of the proximal and middle third of the hepaticocholedochus (p = 0.005; p < 0.001; p < 0.001, respectively) and absence of MPD obstruction (p = 0.022; p < 0.001; p = 0.008, respectively). Female gender is a risk factor for PEP or HA and HA (p = 0.011; p = 0.028, respectively), and catheterization and/or contrast injection into MPD are risk factors for PEP or HA (p = 0.04). Conclusion. Development of PEP in MEHBO depends on the localization of a tumor and involvement of the pancreas. The risk factors for PEP in MEHBO are tumor localization at the level of the middle and proximal third of the hepaticocholedochus and absence of MPD obstruction.