Prognostic nomogram for acute pancreatitis after percutaneous biliary stent insertion in patients with malignant obstruction

Abstract Objective This study aimed to develop and validate a nomogram to predict the risk of pancreatitis after percutaneous transhepatic biliary stent insertion (PTBS) in patients with malignant biliary obstruction (MBO). Materials and methods We enrolled 314 patients who underwent PTBS for MBO from March 2016 to July 2021 in this retrospective study. We used univariate analysis to identify potential risk factors, while a multivariate logistic regression model was employed to establish a nomogram for predicting the risk of pancreatitis. The discrimination and calibration of the nomogram were evaluated by estimating the area under the receiver operator characteristic curve (AUC) and by bootstrap resampling and visual inspection of the calibration curve. The clinical utility of the nomogram was assessed using decision curve analysis (DCA). Results After the procedure, 41 (13.1%) patients developed pancreatitis. Based on multivariate logistic regression analysis, young age (OR = 2.57, 95% CI 1.16 to 5.69), stent insertion across the papilla (OR = 6.47, 95% CI 2.66 to 15.70), and visualization of the pancreatic duct (OR = 15.40, 95% CI 6.07 to 39.03) were associated with an elevated risk of pancreatitis. Importantly, the performance of the nomogram was satisfactory, with an identical AUC (0.807, 95% CI 0.730 to 0.883) and high-level agreement between predicted and observed probabilities as suggested in calibration curves. The DCA curve subsequently confirmed the clinical utility. Conclusion A predictive nomogram for pancreatitis after PTBS in patients with MBO was successfully established in the present study.