Methodology: IHC

Clinical Significance:
Identifies neural cell adhesion molecule (NCAM), a cell surface-associated protein expressed by NK cells and a subset of activated T cells, in addition to a variety of neuroectodermally-derived structures. CD56 is expressed on the majority of NK cell neoplasms, and on a subset of T cell neoplasms. CD56 is aberrantly expressed by myeloid blasts, granulocytes, and/or monocytes in a subset of acute myeloid leukemias and myelodysplastic/myeloproliferative syndromes, and by the neoplastic plasma cells in a large subset of multiple myelomas. Finally, CD56 is strongly expressed by small blue round cell tumors of neuroectodermal origin, and by neuroendocrine carcinomas. Subcellular Localization: Membranous

Organ: Brain/CNS

Disease State: Small, Blue, Round Cell Tumors

CPT Code(s): 88342 or 88341. The CPT codes provided are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payer being billed.

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