For Biliary Dilatation, a Negative Endosonography Needs Additional Image Studies in Weight Loss Suggesting Malignancy

Abstract

Biliary dilatation frequently raises concerns about the possibility of pancreatobiliary diseases. This study assessed the etiologic yield of endosonography (EUS) in this situation. A retrospective review was completed with 163 consecutive patients who had undergone EUS for a dilated common bile duct (CBD) without definite pathology on ultrasonography. Binary logistic regression analysis disclosed that malignancy was positively related to weight loss and was inversely related to abdominal pain; nevertheless, choledocholithiasis was positively related to fever and elevated carbohydrate antigen 19-9 (p < 0.05). The accuracy of EUS was 95.1 % (155/163) for overall cause of biliary dilatation, 100 % (73/73) for no pathological finding, 96.3 % (26/27) for ampullary cancer, 84.6 % (11/13) for pancreatic cancer, 40.0 % (2/5) for CBD cancer, and 92.6 % (25/27) for choledocholithiasis, respectively. The accuracy of EUS decreased in the presence of malignancy (86.7 %, 39/45 vs. 98.3 %, 116/118, p = 0.006). EUS missed three CBD cancers, two pancreatic cancers, and one ampullary cancer; however, the diagnosis was rescued by computed tomography in two pancreatic cancers and one CBD cancer. EUS is accurate in patients with fever suggestive of choledocholithiasis. However, a negative EUS finding should call for additional image studies in patients with weight loss suggestive of malignancy.