Alternative Name
Insulinoma-associated protein 1
Methodology
Immunohistochemistry (IHC)
Test Description
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 & Transportation
Use cold pack for transport. Make sure cold pack is not in direct contact with specimen.
CPT Code(s)*
88342 x 1 or 88341 x 1
Turnaround Time
24 hours
Level of Service
Stain Only
New York Approved
Yes