Defining endoscopic ultrasonography features chronic pancreatitis in asians – a multicenter validation study

Abstract

Background and Objectives:Although endoscopic ultrasonography (EUS) features and criteria have been described in chronic pancreatitis, interoperator variability and ease of adoption limit their usefulness. The aim of the study is to define and validate EUS features of chronic pancreatitis in a multicenter, prospective Asian study.Methods:The study was conducted in two phases. In Phase I, expert endosonographers across Asia reviewed standardized EUS videos of the pancreas for internationally used diagnostic EUS features of chronic pancreatitis. Features that had good overall interobserver agreement were used to derive EUS features for the diagnosis of chronic pancreatitis. These features were then used in Phase II where they were validated in a prospective, multicenter case–control design.Results:For Phase I, thirty endosonographers rated 17 EUS imaging videos of the pancreas for 11 internationally used diagnostic EUS features of chronic pancreatitis. The top six EUS features that had good interobserver agreement (mean κ = 0.73) formed a set of criteria. These include hyperechoic foci with shadowing, lobularity with honeycombing, cysts, dilated ducts, dilated side branches, and calculi in the main pancreatic duct. For Phase II, 284 subjects (132 cases, 152 controls) were enrolled from 12 centers. All six features were useful with high accuracy ranging from 63.3% to 89.1%. Using the receiver operating curve, two or more of these six EUS features accurately define chronic pancreatitis (sensitivity 94.7% specificity 98.0%), with an area under the receiver operating characteristic curve of 0.986.Conclusion:This study thus defines and prospectively validates Asian criteria for chronic pancreatitis.