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PSA (prostate-specific antigen) testing: what it means for you

Waiting on test results can feel like one more hard thing, for you and the people who love you. Here's what the PSA (prostate-specific antigen) test looks for and how it can help your care team pick the treatment most likely to work for you.

ℹ️ General information to help you and your loved ones talk with your care team, not medical advice. Read our disclaimer.

Matters most in: Prostate cancer

Why it matters

PSA helps with screening, with deciding how serious a prostate cancer may be (along with the Gleason score and stage) and, most of all, with tracking how well treatment is working. A rising PSA after treatment can be the first sign the cancer is active again, often before scans show anything.

Treatments it can point to

• PSA results guide decisions on active surveillance, hormone therapy and drugs like Xtandi (Xtandi (enzalutamide))

Only your care team can say which treatment fits you. Drug approvals depend on cancer type, stage and prior treatment.

Tissue vs. blood testing

A simple blood test, repeated over time. Trends matter more than a single number.

Most tests use a piece of tumor tissue from a biopsy or surgery. Some can also use a blood sample (a 'liquid biopsy') that looks for tumor DNA floating in the blood. Blood tests are easier and faster, but they can miss a change that a tissue test would find, so a negative blood test is often followed by a tissue test.

❓ Questions you and your loved ones can ask

• What is my PSA, and how fast is it changing?
• What PSA level would make us change treatment?
• When will my results be back, and will treatment wait for them?
• Will my insurance cover this test?

Written by the Cancer Side Effects Guide team from FDA labels and leading cancer centers. Not medical advice. · Last updated: October 15, 2026 · How we write