CD56

Formalin-fixed, paraffin embedded tissue block or cell block, or 1 unstained charged slide for each test requested plus 3-4 additional unstained slides cut at 4 microns. Adequate space on each slide for control tissue is required.

CD56 is a membrane glycoprotein which as multiple isoforms generated by alternative splicing from a single gene. The predominant 140kDa isoform is expressed by NK and a subset of T cells and their lymphomas. It is identical to the neuronal cell adhesion molecule (NCAM) found in cells and small blue cell tumors of neuroectodermal origin as well as neuroendocrine carcinomas. CD56 is also aberrantly expressed in a subset of acute myeloid leiukemia and multiple myeloma.