IMMUNOHISTOCHEMISTRY, CK 5 / 6

What this test checks

Detects cytokeratin 5 and 6 proteins in tissue, which are characteristic of certain cell types — particularly squamous cells and basal/myoepithelial cells. Used to classify tumour cell type and origin.

Why do people get this test?

CK5/6 helps distinguish squamous cell carcinomas and basal-type breast cancers from other tumour types, ensuring accurate diagnosis and appropriate treatment.

When you should consider this test

• When classifying lung cancer subtype (squamous vs. adenocarcinoma)
• When identifying basal-like or triple-negative breast cancer
• When distinguishing mesothelioma from other chest tumours

How to prepare

No preparation needed — performed on biopsy or surgical tissue.