S0026 Predictors for Improvement of Chronic Pancreatitis Symptoms After Single Operator Pancreatoscopy With Intraductal Lithotripsy or Extracorporeal Shock Wave Lithotripsy for Large Main Pancreatic Duct Stones

Abstract

INTRODUCTION: Main pancreatic ductal stones (MPDS) complicate chronic pancreatitis (CP), leading to disabling symptoms such as intractable pain and exocrine pancreatic insufficiency (EPI). Large MPDS (≥5 mm) are more difficult to extract and require lithotripsy with either single operator pancreatoscopy with intraductal lithotripsy (SOPIL) or extracorporeal shock wave lithotripsy (ESWL). This study aims to identify clinical predictors for improvement of CP symptoms after MPDS lithotripsy. METHODS: We retrospectively identified CP patients from 9/2013 to 9/2019 who underwent SOPIL or ESWL for MPDS therapy at our center. Electrohydraulic lithotripsy (EHL) was used for SOPIL. Successful stone clearance was defined as >80% stone fragmentation and extraction. Clinical outcomes: patient reported pain improvement at follow-up, improvement of EPI defined by cessation of enzyme supplementation. Possible predictors identified in univariate logistic regression models (P-value < 0.25) were subsequently used in multivariable logistic regression models, with significance defined as P-value < 0.05. RESULTS: Of the 217 MPDS patients managed with lithotripsy, technical success occurred in 189/217 (87.1%). Pain improvement occurred in 168/197 (85.3%). Exocrine insufficiency was present in 109 and pancreas enzyme supplementation was able to be discontinued in 8 (7.3%) after stone clearance. Analysis for predictors of pain improvement (Table 1) identified concurrent exocrine insufficiency, alcohol etiology, idiopathic etiology, and technically successful stone clearance as possible predictors. On multivariable analysis, technical success was highly predictive of pain improvement (OR 196.57 [41.322–935.10], P < 0.001). Analysis for predictors of EPI improvement identified multiple possible predictors (Table 2). On multivariable analysis, a SOPIL approach (OR 43.565 [3.146–603.34], P = 0.005) predicted EPI improvement and upstream PD diameter increase by every 1 mm was a negative predictor for EPI improvement (OR 0.512 [0.284–0.925], P = 0.026).Table 1.: Univariate and multivariable logistic regression model assessing predictors of pain improvement in patients who underwent single operator pancreatoscopy with intraductal lithotripsy (SOPIL) or extracorporeal shock wave lithotripsy (ESWL).Table 2.: Univariate and multivariable logistic regression model assessing predictors of exocrine pancreatic insufficiency improvement (defined by cessation of pancreatic enzymes supplementation) in patients who underwent single operator pancreatoscopy with intraductal lithotripsy (SOPIL) or extracorporeal shock wave lithotripsy (ESWL). CONCLUSION: Technical success of lithotripsy for MPDS predicted improvement of baseline abdominal pain in CP independent of other clinical factors. A SOPIL over ESWL approach independently predicted improvement of EPI symptoms. Upstream main pancreatic duct diameter as a possible surrogate marker for duration of obstruction and organ atrophy is a negative predictor for resolution of EPI symptoms after lithotripsy approaches for MPDS.