Intestinal and pancreatobiliary differentiation in periampullary carcinoma: the role of immunohistochemistry

Histomorphologic and molecular phenotypes predict gemcitabine response and overall survival in adenocarcinoma of the ampulla of Vater

“…Immunohistochemical characterization of PapCa has been performed previously to objectify histopathologic stratification. 2,27,28 In general, our immunohistochemical results are in line with those of Kumari et al, 29 who state that a panel of immunohistochemistry markers is primarily not helpful to classify PapCa subtypes because classification can be performed in a satisfactory manner simply on the basis of morphology. In undetermined (ie, high-grade) cases, however, it might be helpful to amend routine assessment and to determine the predominant phenotype in mixed- type tumors.…”

Difficult Diagnostic Problems in Pancreatobiliary Neoplasia

“…29 Among these markers, CDX2, MUC1, and MUC2 are particularly reliable, and the keratin stains are relatively unreliable. 30 However, these markers may be less effective in distinguishing among phenotypes in ampullary neoplasia than in pancreatic intraductal papillary mucinous neoplasms (IPMNs) given the mix of cell types normally found at the ampulla. 27 Notably, cancerization of the ampullary, bile ductular, and duodenal epithelium by PDAC may occur and can be difficult to distinguish from primary carcinoma in situ.…”

“…At a minimum, documentation of differentiation (intestinal, pancreatobiliary, or mixed) should be reported because studies have shown that intestinal-type ampullary carcinomas carry a better prognosis than do pancreatobiliary-type tumors. 30,[33][34][35] However, the optimal method of distinguishing the intestinal from the pancreatobiliary phenotypes remains to be determined-through morphology alone or through a combination of morphology and immunohistochemistry. A recent analysis 36 used a combination of CDX2, MUC1, and morphology to separate pancreatobiliary…”

Mixed adenoneuroendocrine carcinoma of the ampulla of Vater: A case report

“…Among these, two predominant subtypes of adenocarcinoma have been identified, which show either pancreaticobiliary (15-20%) or intestinal differentiation (50-80%) (2,3). Subclassification is clinically relevant, since in addition to advanced tumour stage and poor differentiation, the pancreaticobiliary subtype has been identified as an adverse prognostic factor (2,(4)(5)(6). Tumours with neuroendocrine differentiation, including neuroendocrine tumours and neuroendocrine carcinomas (NECs) are only rarely observed at this site (4,7,8).…”