GFAP

Glial Fibrillary Acidic Protein (GFAP), an intermediate filament protein expressed almost exclusively in glial cells and tumors of the central nervous system. Gliomas are the most common cerebral neoplasm in adults and include astrocytomas, oligodendrogliomas and glioblastomas. It can also be demonstrated in ependymal cells, ependymomas, subependyomas, glioblastomas, mixed central nervous system neoplasms, and gangliomas. It is detected in immature but not mature oligodendrocytes and neurons, and anti-GFAP antibodies do not cross-react with neurons, fibroblasts, or muscle cells. These antibodies are useful in differentiating primary gliomas from metastatic lesions in the brain and for documenting astrocytic differentiation in tumors outside the central nervous system. GFAP is also expressed in a restricted subset of epithelial tumors, including salivary gland pleomorphic adenomas.

Synonyms
Glial Fibrillary Acidic Protein
Turnaround Time
24 hrs
Methodology
IHC
Specimen Requirements

A formalin-fixed, paraffin-embedded (FFPE) tissue block is preferred specimen typeorOne (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 orderedBlock 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 Codes
88342 x 1 or 88341 x 1