Alternate Test Names:
CD117; Stem Cell Receptor; ckit

Methodology: IHC

Clinical Significance:
c-kit, also known as stem cell receptor, is a protein kinase transmembrane receptor that is a marker of gastrointestinal stromal tumors and a mutant form of which is a target of Imatinib therapy. Wild type c-kit expression is present in mast cells, melanocytes, germ cells, glandular epithelium of the breast and salivary gland, and normal interstitial cells of Cajal of the intestine.

Subcellular Localization: Membranous

Organ: Colon & Other GI, Genitourinary, OB/GYN

Disease State: Germ Cell Tumors, Mastocytosis, Spindle Cell Tumors / Sarcoma Subtyping

CPT Code(s): 88342 or 88341 (reference only; CPTs may vary)

Turnaround Time: Within 1-2 business days of receipt

Schedule: Monday - Friday

Specimen Requirements:
• Formalin-fixed, paraffin-embedded (FFPE) tissue block or cell block - OR -
• 1 unstained slide for each test requested plus 3-4 additional unstained slides cut at 4µm