IMMUNOHISTOCHEMISTRY, CD 56

What this test checks

Detects CD56 (NCAM — Neural Cell Adhesion Molecule), expressed in natural killer (NK) cells, neuroendocrine cells, and some neuroblastomas. Used to classify NK/T-cell lymphomas and confirm neuroendocrine differentiation.

Why do people get this test?

NK/T-cell lymphoma is an aggressive tumour most common in Asia. CD56 positivity, combined with EBV testing, confirms this diagnosis — guiding specific (L-asparaginase-based) chemotherapy protocols.

When you should consider this test

• When NK/T-cell lymphoma is suspected
• When confirming neuroendocrine differentiation in tumours
• When classifying neuroblastoma in children

How to prepare

No preparation needed — performed on biopsy or surgical tissue.