Prostatic Specific Antigen (Total)

Function

Prostate-Specific Antigen (PSA) is a protein produced by both normal and malignant cells of the prostate gland. PSA liquefies semen, allowing sperm to swim freely. While most PSA is found in semen, small amounts circulate in the blood, which can be measured to monitor prostate health.

Why it is Ordered

The Total PSA test is used primarily to screen for prostate cancer in men. It is also utilized to monitor patients with a known history of prostate cancer to check for recurrence after surgery or radiation. Additionally, it helps in diagnosing and monitoring inflammation of the prostate (prostatitis) or non-cancerous enlargement (Benign Prostatic Hyperplasia, or BPH).

Associated Conditions

• Prostate Cancer: Higher levels of PSA correlate with an increased risk of malignancy.
• Benign Prostatic Hyperplasia (BPH): As the prostate grows larger with age, PSA levels naturally rise.
• Prostatitis: Infection or inflammation of the gland can cause sharp, temporary spikes in PSA levels.

Interpretation Nuance

PSA is not a definitive 'cancer test.' Many men with elevated PSA do not have cancer, and some men with low PSA do. Doctors look at the 'PSA Velocity' (rate of change over time) and 'PSA Density' (PSA level relative to the size of the prostate) to make more informed clinical decisions.