IMMUNOHISTOCHEMISTRY, P63

What this test checks

Detects p63 protein, which marks squamous cells and myoepithelial cells. Used to identify squamous cell carcinomas and to check for the presence of myoepithelial cells in breast tissue (a sign of benign disease).

Why do people get this test?

P63 helps distinguish squamous cancers from other cancer types and can confirm benign breast lesions — both critical for treatment decisions.

When you should consider this test

• When classifying lung cancer (squamous vs. adenocarcinoma)
• When evaluating breast lesions for benign vs. malignant features
• When identifying head and neck squamous cell carcinoma subtype

How to prepare

No preparation needed — performed on biopsy or surgical tissue.