Usually demonstrated as a linear labeling of the apical poles of cells lining the glandular lumen and occasionally as weak staining near the apex of normal colonic epithelial cells. It is expressed by a subset of epithelial cells and carcinomas, and pancreatic carcinomas, testicular tumors, gallblader neoplasms and grandular cell myoblastomas all stain positive, while malignant tumors of brain, prostate, skin, lymphoreticular tissues, hepatocellular carcinomas, esophageal squamous cell carcinomas, and mesothelioma fail to stain. Tumors tend to display an increased cytoplasmic staining.
A formalin-fixed, paraffin-embedded (FFPE) tissue block is preferred specimen typeorOne (1) unbaked, unstained slide for H&E staining (required) and two to three (2-3) positively charged unstained slides (all cut at 4-5 microns) for each test/antibody orderedBlock and slide identifiers should be clearly written and match exactly with the specimen ID and specimen labeling as noted on the requisition.
Use cold pack for transport. Make sure cold pack is not in direct contact with specimen.