LEFT: 71 year-old woman with painless jaundice. Computerized tomography showed dilation of biliary and pancreatic ducts; the head of the pancreas had a prominent appearance. Endoscopy revealed nodular deformity in the periampullary duodenum; the ampulla itself (arrow) was grossly normal. Biopsies of the duodenal mucosa revealed invasive adenocarcinoma, which was most likely of pancreatic origin.

RIGHT: 76 year-old woman who had been found to have a large duodenal polyp three years previously; at that time biopsies were consistent with a benign adenoma without dysplasia, and she was advised to return for complete polypectomy. She was lost to follow-up for three years. Repeat endoscopy revealed enlargement of the polyp, although the gross appearance was still benign. The lesion was resected endoscopically, but there was a small focus of adenocarcinoma within 4 mm of the margin.