Sphincter of Oddi dysfunction caused by an ampullary neoplasm.

The case of a 50-year-old man with abdominal pain and abnormal liver test results is described. Endoscopic retrograde cholangiopancreatography with manometric studies showed biliary dilatation, poor ductal drainage, and sphincter of Oddi dysfunction. Clinical and radiographic clues suggested the possibility of an ampullary lesion; a small ampullary adenoma was detected after endoscopic sphincterotomy, and ampullary carcinoma was found in the operative specimen. Malignancy can cause sphincter dysfunction not only in the esophagus (as pseudoachalasia) but in the ampulla of Vater as well.