Bulky gastrinoma of the common bile duct: unusual localization of extrapancreatic gastrinoma--case report.

Zollinger-Ellison syndrome is characterized by elevated levels of serum gastrin associated with increased gastric acid secretion, gastrointestinal ulcerations and diarrhea. Most gastrinomas (75%) occur sporadically and are located within the gastrinoma triangle. Extraduodenal, extrapancreatic and extranodal gastrinomas have been shown in 5.6% of the patients with Zollinger-Ellison syndrome who underwent surgery. We report a 44-year-old female who had been complaining of nausea and diarrhea for 12 years. Abdominal computed tomography and magnetic resonance imaging detected a homogeneous, regular-shaped 6 x 7 cm solid mass, located between the liver, right kidney and inferior vena cava. Somatostatin receptor positive scanning led us to investigate a neuroendocrine tumor. Serum gastrin level was found very high and the patient underwent surgery. Local excision of the tumor was performed, and an 8x6x5 cm, well-capsulated, solitary mass, originating from the common bile duct was removed. The unique feature of our case is the unusual localization, and although the tumor was very large in size, only capsule invasion was observed with no evidence of distant metastasis.