IMMUNOHISTOCHEMISTRY, PROSTATE SPECIFIC ANTIGEN (PSA)

What this test checks

Detects PSA protein in tissue to confirm prostate cancer origin — particularly useful when cancer has spread and the primary site needs to be identified.

Why do people get this test?

When cancer has metastasised to bone, lymph nodes, or other sites, PSA immunostaining on tissue confirms prostate as the origin — directing treatment to hormone therapy and prostate cancer-specific drugs.

When you should consider this test

• When metastatic cancer of possible prostate origin needs confirmation
• When classifying an undifferentiated tumour in a male patient
• As part of prostate cancer diagnostic panel in tissue

How to prepare

No preparation needed — performed on biopsy or surgical tissue.