Figure 1

(a) Ampullary carcinoma with intestinal features. Note the presence of large tubules lined by tall columnar cells with elongated, pseudostratified, hyperchromatic nuclei resembling colonic-type adenocarcinoma. Luminal necrotic debris and acute inflammatory cells are also present. (b) Ampullary carcinoma with pancreatobiliary features. Small widely separated glands are lined by low cuboidal eosinophilic epithelium with a high nuclear to cytoplasmic ratio, and round nuclei with vesicular chromatin and irregular nuclear contours.