title: Intraoperative ultrasonic localization of endocrine tumors of the pancreas.
abstract: Small endocrine tumors of the pancreas can be located before operation by computerized tomography, ultrasonography, angiography, or percutaneous transhepatic venous sampling for hormone assay; to these may eventually be added nuclear magnetic resonance studies. Precise preoperative localization of insulinomas is possible in 80% to 90% of the cases if a stepwise approach combining these methods is used. In as many as 10% of the patients with organic hyperinsulinism and as many as 50% of the patients with Zollinger-Ellison syndrome problems are encountered during the operation because either the tumor cannot be palpated or there are multiple tumors. Only 25% of the multiple tumors are known by angiography before operation. Forty percent of the tumors have a diameter of less than 1 cm. Numerous methods have been reported for intraoperative localization of endocrine pancreatic neoplasms.
mesh_terms: D007516:Adenoma, Islet Cell / Q000601:surgery*; D006801:Humans; D007340:Insulinoma / Q000175:diagnosis / Q000601:surgery*; D007432:Intraoperative Period; D010190:Pancreatic Neoplasms / Q000175:diagnosis / Q000601:surgery*; D014463:Ultrasonography; D015043:Zollinger-Ellison Syndrome / Q000175:diagnosis / Q000601:surgery*