CD56 (MRQ-42)

CD56, known as neural cell adhesion molecule (NCAM), was originally identified in the nervous system and belongs to a group of cell adhesion molecules including cadherins, selectins, and integrins. Anti-CD56 recognizes two proteins of the NCAM, the basic molecule expressed on most neuroectodermally-derived cell lines, tissues and neoplasms (e.g. neuroblastomas, small cell carcinomas). It is also expressed on some mesodermally-derived tumors (rhabdomyosarcoma). Furthermore, anti-CD56 has found great utility in the recognition of NK cell and NK/Tcell lymphomas. It has been shown that 71% of myelomas are positive for anti-CD56 as well. It also offers higher sensitivity in the diagnosis of small cell carcinoma than anti-chromogranin and anti-synaptophysin. Light staining of smooth muscle elements may be seen.1-9