Primary carcinoid tumour of the common bile duct

Background: Carcinoid tumours of the extrahepatic biliary tree are exceedingly rare. We report a case of primary carcinoid tumour arising in the distal portion of the common bile duct. Case outline: A 30-year-old man was admitted with watery diarrhoea and symptoms of biliary obstruction. Abdominal ultrasound scan showed a normal gallbladder without stones, mild dilatation of the intra- and extrahepatic biliary tree and a 2 cm solid lesion in the head of pancreas compressing the distal common bile duct. Computed tomography confirmed these findings and showed that the tumour was hypervascular. Gastrointestinal hormone screening showed an increase in plasma serotonin. The patient underwent a standard pylorus-preserving proximal pancreatoduodenectomy (PPPD). Results: Pathological examination showed a neuroendocrine tumour (carcinoid) of the distal bile duct. The postoperative plasma serotonin decreased to normal levels. One year later the patient is well without evidence of disease. Discussion: Primary carcinoid tumours of the extrahepatic biliary tree are rare, accounting for 0.2-2% of all digestive carcinoids. This is the fifth report of a tumour arising from the distal common bile duct. Surgical treatment for neoplasms of the distal common bile duct can be problematic because of the site of the lesion and the difficulty in differentiating them from periampullary neoplasms lesions. Pancreatoduodenectomy (PD) is therefore the treatment of choice.