Ampullary tumors: radiologic-pathologic correlation.

Ampullary adenoma and adenocarcinoma are the benign and malignant neoplasms that arise from the glandular epithelium of the ampulla of Vater. When the tumors are small and confined to the ampulla, endoscopic and radiographic appearances may be normal. Larger intraampullary tumors appear as a prominent papilla or a mural mass. Computed tomography and ultrasound (US) show dilatation of the common bile duct or pancreatic duct in such cases, but the mass itself may not be seen. Larger lesions with intraduodenal extension are more easily identified with cross-sectional imaging. Endoscopic US is the best technique for tumor staging. The differential diagnosis includes other periampullary tumors such as pancreatic carcinoma, cholangiocarcinoma, and villous adenomas and adenocarcinomas of the duodenum. Mural masses of the periampullary duodenum including choledochocele and carcinoid should also be considered. Accurate diagnosis of ampullary tumors is important because the patients are usually candidates for a Whipple operation. Recent reports quote overall 5-year survival rates of 28%-70%. The prognosis is even better for patients with a limited stage of disease.