The Use of Radial Endosonography Findings in the Prediction of Cholangiocarcinoma in Cases with Distal Bile Duct Obstructions

Background/Aims: We retrospectively collected the data of radial endosonographic (EUS) imaging findings of the patients with the distal bile duct obstructions due to different benign and malignant conditions. We aimed to assess and analyze the EUS findings in the distal bile duct obstruction which can predict or detect the existence of cholangiocarcinoma originating from the distal bile duct wall. Methodology: We gathered the data of 192 cases with distal biliary stricture due to various causes which all were diagnosed. Results: With EUS, The sensitivity and specificity for diagnosis of cholangiocarcinoma in lesions were respectively as following: Firstly, small hypoechoic mass which interrupts to see lumen and choledoch wall with total occlusion at distal choledoch: 75.8%, 88.1%. Secondly, hypoechoic and irregular thickening than surrounding regions at distal choledoch wall: 68.1%, 87.3%. Thirdly, appearance of lumen prompt termination at distal choledoch: 57.1%, 87.6%. Lastly, appearance where lumen narrows short segment: 13.6 %, 59.3 %. Conclusions: EUS findings including hypoechoic mass appearance completely occluding the lumen or heterogeneously increased irregular wall-thickness in the distal bile duct were found to be highly predictive and sensitive for detecting malignancy originating from the distal bile duct.