Comparative histologic and immunohistochemical classification of ampullary carcinoma and on endoscopic biopsy resection specimens

Junctions of two different types of epithelia can give rise to tumors which may show features of either of the colliding epithelia or a mixture or intermediate of both. One such junction is the ampulla of Vater, the luminal opening of common channel formed by the common bile duct and the main pancreatic duct of Wirsung within the wall of the duodenum. Here the pancreatic and bile duct epithelia meet the duodenal mucosa at the ampulla(1). Tumors involving the ampulla could be arising primarily in the ampulla or extending from the adjacent sites like duodenum, bile duct and pancreas. Tumors arising at any of these sites can present as an ampullary/ periampullary growth. When a neoplasm is centered primarily in the ampulla with or without periampullary mucosal involvement, it is considered a primary ampullary carcinoma (2). These tumors generally have a better prognosis compared to duodenal and pancreaticobiliary neoplasms secondarily involving the ampulla Santini D, Vincenzi B, Tonini G, et al. Cyclooxygenase -2 overexpression is associated with a poor outcome in resected ampullary cancer patients. Clin Cancer 2005; 11: 3784-89. 43. Gheza F, Cerv E, Pulcini E et al. Signet ring cell carcinoma of Ampulla of Vater: Demonstration of pancreaticobiliary origin. Pancreas . 2011; 40:791-3. 44. Fischer HP, Zhou H. Pathogenesis of carcinoma of the papilla of Vater. J Hepatobiliary Pancreat Surg. 2004;11(5):301-9. 45. Painter JT, Clayton NP and Herbert RA. Useful immunohistochemical markers of tumor differentiation. Toxicol. Pathol. 2010; 38: 131-41. 46. Bayrak R, Yeni Dunya S and Haltas H. Ck 7 and CK 20 expression in colorectal adenocarcinomas. Pathol. Res. Pract. 2011; 207:156-60