A traumatic neuroma of the bile duct: a case report.

Traumatic neuroma of the bile duct is not a true neoplasm, but a reactive proliferation of pericholangial nerve tissue induced by injury. A 60-year-old Japanese man was admitted to investigate obstructive jaundice. He had undergone cholecystectomy and common bile duct exploration 17 years previously. Ultrasonography and computed tomography showed a pneumobilia with dilatation of the intrahepatic biliary ducts. Endoscopic retrograde cholangiography and spiral-computed tomography cholangiography revealed biliary stenosis in the hepatic hilus with dilatation of the intrahepatic biliary ducts. Celiac angiography and arterial portography showed neither tumor stains nor signs of vessel invasion. At surgery, the confluent portion of the intrahepatic biliary ducts in the hepatic hilus was hardly palpable and deformed, but frozen-section microscopic examination confirmed that no malignant cells were present. Anastomosis of the right and left extrahepatic bile duct to the jejunum, reconstructed by Roux-en-Y hepaticojejunostomy, was performed. Histological examination revealed a nodule composed of a haphazard proliferation of nerve fascicles in the fibromuscular layer of the bile duct which were positively stained for S-100 protein. The pathological diagnosis was traumatic neuroma of the bile duct. Thus, the possibility of traumatic neuroma should be considered in the differential diagnosis of patients with late-onset jaundice after biliary tract surgery.