Test Method


CPT Code

88342 x 1
88341 x 1

Stains / Test Description

CD31 is a 130kDa transmembrane glycoprotein that is shared by vascular lining cells, megakaryocytes and platelets. This marker has excellent sensitivity and is highly restricted to endothelial neoplasms among all tumors of soft tissue. 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.

Specimen Requirements

(1) H&E slide with formalin-fixed, paraffin-embedded (FFPE) tissue, fixed with 10% NBF.
One (1) unbaked, unstained slide for H&E staining (required) and two to three (2-3) positively charged unstained slides (all cut at 4 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.

Storage & Transport

Ship specimen same day (whenever possible) with refrigerated (not frozen) cold pack

Turnaround time

1-3 days depending on level of service

Level of Service

Global (with interpretation)
Slide Only (glass slides only)
Web-Enabled (glass and digital images through eCSI portal)