Methodology
Immunohistochemistry (IHC)
Test Description
DOG1 is a cell surface protein of unknown function selectively expressed in gastrointestinal stromal tumors (GIST). Among GIST cases with Kit mutations the DOG1 antibody identified 11% more cases than c-Kit antibody. DOG1 identifies the vast majority of both cKIT negative and Platelet-derived Growth Factor Receptor Alpha (PDGFRA) mutated GIST cases that may still benefit from imatinib mesylate (Gleevec®), an inhibitor of the Kit tyrosine kinase. In addition, DOG1 immunoreactivity is seen in fewer cases of mesanchymal, epithelial tumors and melanomas when compared with cKIT. The use of this highly sensitive and specific novel marker will increase the accuracy of GIST diagnosis.
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. 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

*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.