Get in touch
Our Client Services team is on hand to help. Please call us at 866.776.5907, Option 3.
INSM1
- Immunohistochemistry (IHC)
INSM1 is a transcription factor that is a sensitive and specific marker for neuroendocrine tumors. It is a nuclear stain, and is as good if not better than synaptophysin and is superior to chromogranin. It is rarely expressed on adenocarcinoma or squamous cell carcinomas without neuroendocrine differentiation.
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)*
88342 x 1 or 88341 x 1
*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: August 12, 2025