A case of benign tumor (adenomyomatous hyperplasia) of common bile duct

Abstract

Benign bile duct tumors are very rare. In Japan only 25 cases have been reported to date.
Recently we discovered a bile duct tumor, an adenomyomatous hyperplasia, by ERCP. A slight dilatation of the common bile duct was noted during abdominal ultrasonography. Based on the histopathologic findings of our biopsy specimen, the patient was spared surgery. This case shows that preoperative, morphologic diagnosis of benign bile duct tumors by the various imaging techniques of the biliary system alone remains difficult. An interventional approach by endoscopic examination of the biliary system and other methods such as PTCS with biopsy is important.
Furthermore, an aggressive attitude towards performing ERCP routinely even for slight dilatation of the bile duct found during abdominal ultrasonography will improve the rate of diagnosis of small tumors of the bile duct.