Endosonography in diagnosing and staging duodenal villous adenoma.

Endosonography was carried out in a patient with an extensive juxtapapillary tumour. Radiology and endoscopy were unable to distinguish a villous adenoma from an invasive carcinoma. Endosonography revealed a mucosal hypoechoic tumour without penetration into the submucosa and muscularis propria. The common bile duct, pancreatic duct, and pancreas were normal. Lymph node abnormalities were not found. Based on the endosonography findings, local surgical tumour resection was undertaken instead of a Whipple procedure. The histology of the resected specimen confirmed the endosonography diagnosis.