IMMUNOHISTOCHEMISTRY, P16

What this test checks

Detects p16 protein, which is often overexpressed in HPV (human papillomavirus)-related cancers — particularly cervical cancer and HPV-positive head and neck cancers. Used to confirm HPV-driven tumours.

Why do people get this test?

HPV-positive cancers (especially oropharyngeal cancers) have a better prognosis and may respond to different treatment intensities. P16 is the standard surrogate marker for HPV positivity in these settings.

When you should consider this test

• When classifying head and neck squamous cell carcinoma (oropharyngeal cancer)
• When assessing cervical cancer for HPV association
• When determining prognosis and treatment intensity for oropharyngeal cancer

How to prepare

No preparation needed — performed on biopsy or surgical tissue.