CD31 is a 130kDa transmembrane glycoprotein that is shared by vascular lining cells, megakaryocytes and platelets. This marker is highly restricted to endothelial neoplasms among all tumors of the soft tissue and its sensitivity is excellent. 100% of angiosarcomas and hemangiomas are CD31 positive. However, Kaposi’s sarcoma (KS) is labeled more consistently by CD34 than by CD31. CD31 has also been used as a prognostic marker measuring tumor angiogenesis. CD31 also stains histiocytes.
- A formalin-fixed, paraffin-embedded (FFPE) tissue block is preferred specimen type
- One (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 ordered
- Block 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.