• Immunohistochemistry (IHC)
Calretinin is the most specific and reproducible positive marker of epithelial mesothelioma. Calretinin is a calcium-binding protein similar to S100 protein. It is found in the central and peripheral nervous system and in a wide spectrum of non-neural cells, including steroid-producing cells of ovaries and testes, fat cells, renal tubular epithelial cells, eccrine glands, thymic epithelial cells and mesothelial cells. Calretinin immunostaining is found in most epithelial mesotheliomas.
Turnaround time
1 Day

Level of Service

  • Technical Only
New York Approved: Yes

Specimen Requirements

A formalin-fixed, paraffin-embedded (FFPE) tissue block is preferred specimen type or 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.

Storage and Transportation

Use cold pack for transport, making sure cold pack is not in direct contact with specimen. NYS clients please provide date and time of Collection.

CPT Code(s)*

88342x1or 88341x1

*The CPT codes provided with our test descriptions are based on AMA guidelines and are for informational purposes only. Correct CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed.

Last Updated: January 22, 2025

Get in touch

Our Client Services team is on hand to help. Please call us at 866.776.5907, Option 3.