Table 1.
Immunohistochemical staining pattern in the present case
| Antibody | Gastric tumor site | Gastric heterotopic pancreas site | Description & use of antibody |
| CEA | (+) | (++) | Oncofetal antigen in gastrointestinal, breast, lung, pancreas and other cancers. |
| CA 19-9 | (-) | (-) | Useful cerum marker in gastrointestinal and pancreatic cancer; strongest staining in pancreatic cancer. |
| Cytokeratin 7 | (+) | (++) | Typically found in simple epithelia from the GI tract; lesser degree of expression in gastric cancer. |
| Cytokeratin 19 | (+) | (-) | Cytokeratin filament in a large number of epithelial cell types, including many ductal and glandular epithelia. |
| Cytokeratin 20 | (±) | (-) | Restricted expression in intestinal epithelium, gastric foveolar epithelium and others; lesser degree of expression in pancreatic cancer. |
| MUC1 | (-) | (+) | Glycoprotein of glandular epithelial tissues; modifications to glycosylation of musins in cancer; "gastric mucin" & "PanINs mucin". |
| Ki-67 | (++) | (-) | The assessment of cell proliferation in neoplastic cell populations |
CA, carbohydrate antigen; CEA, carcinoembryonic antigen; MUC, mucin (transmembrane glycoprotein tumor antigen); -, < 5% cells stained; +, 30–70% cells stained; ++, > 70% cells stained; ±, 5–30% cells stained; GI, gastrointestinal; PanIns, pancreatic intraepithelial neoplasias