Nomogram for prediction of adverse events after lumen-apposing metal stent placement for drainage of pancreatic fluid collections

Objectives To generate a prognostic model based on a nomogram for adverse event (AE) prediction after lumen-apposing metal stents (LAMS) placement in patients with pancreatic fluid collections (PFC). Methods Data from a large multicenter series of PFCs treated with LAMS placement were retrieved. AE (overall and excluding mild events) prediction was calculated through a logistic regression model and a nomogram was created and internally validated after bootstrapping. Results were expressed in terms of odds ratio (OR) and 95% confidence interval (CI). Discrimination was assessed by c-statistics and calibrated by comparing deciles of predicted and observed ORs. Results Overall, 516 patients were included (males 68%, mean age 61.6 +/- 15.2 years). PFCs were predominantly walled-off necrosis (52.1%). Independent predictors of AE occurrence were injury of main pancreatic duct (OR in the case of leak 2.51, 95% CI 1.06-5.97, P = 0.03; OR in the case of complete disruption 2.61, 1.53-4.45, P = 0.01), abnormal vessels (OR in the case of perigastric varices 2.90, 1.31-6.42, P = 0.008; OR in the case of pseudoaneurysm 2.99, 1.75-11.93, P = 0.002), using a multigate technique (OR 3.00, 1.28-5.24; P = 0.05), and need of percutaneous drainage (OR 2.81, 1.03-7.65, P = 0.04). By nomogram, a score beyond 200 points corresponded to a 50% probability of AE occurrence. The model was confirmed even when excluding mild AEs and it showed optimal discrimination (c-index 76.8%, 95% CI 74-79), confirmed after internal validation. Conclusion Patients with preprocedural evidence of pancreatic duct leak/disruption, vessel alteration, requiring percutaneous drainage or a multigate technique are at higher risk for AE.

Automated summary

This study aimed to develop a prognostic model for adverse events (AE) after lumen-apposing metal stents (LAMS) placement in patients with pancreatic fluid collections (PFC). Through data collection and analysis, it was found that AE occurrence in PFC patients was associated with factors such as injury to the main pancreatic duct, abnormal vessels, surgical technique, and the need for preprocedural drainage. A nomogram was used to predict the probability of AE occurrence, and the model showed good discrimination and was validated internally.