7017 Capability of performing eus in the patient who have abnormal findings at distal common bile duct and common channel on ercp.

Background: It is difficult to judge whether abnormal findings in the distal common bile duct (CBD) and/or common channel, such as irregularity of the bile duct wall, on endoscopic retrograde cholangiopancreatography (ERCP) are benign or malignancy. The aim of this study was to evaluate the ability of endoscopic ultrasonography (EUS) to identify a malignant tumor in the distal CBD. Patients and Method: EUS was performed on 16 patients in whom ERCP indicated the possibility of a malignant tumor in the distal CBD and/or common channel. Cases in which a tumor was not detected by EUS were judged to be negative if the findings did not change over a one-year follow-up period. Results: The accuracy of EUS for identifying a tumor in the distal CBD was 81.3% (13/16), the sensitivity was 100% (16/16), the specificity was 76.9% (10/13), the positive predictive value was 50% (3/6), and negative predictive value was 100% (10/10). Three cases were misdiagnosed due to tumorous findings; debris, numerous small stones, and inflammation, respectively. Conclusion: EUS is reliable for identifying of the tumor in the distal CBD and/or common channel. EUS should be performed if ERCP indicates the possibility of a tumor in the distal CBD and/or common channel. If EUS findings are negative, it is reasonable to conclude that there is no tumor. If EUS findings are positive, biopsy or cytology should be performed.