Prostate-Specific Antigen Blood Test (PSA Test)

What Is It?

The prostate-specific antigen blood test (PSA test) is a screening test. It measures the amount of prostate-specific antigen (PSA) in a man's blood.

PSA is a chemical made by the prostate. The prostate is a sex gland located near a man's bladder. It produces the fluid in semen.

PSA levels normally increase as a man ages. But a higher-than-normal PSA level can be one clue that cancer has developed in the prostate gland.

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