Free PSA is a specific form of prostate-specific antigen (PSA) found in the blood. Unlike total PSA, which includes both free and bound PSA, free PSA measures the amount of PSA that is not attached to proteins in the blood. This test is often used alongside total PSA levels to provide more information about prostate health, particularly in men with elevated PSA levels.
Understanding free PSA is important because it helps doctors determine the likelihood of prostate cancer in men who have an elevated total PSA level. A higher percentage of free PSA may suggest a lower risk of prostate cancer, while a lower percentage may indicate a higher risk. This distinction can help guide further testing and decisions regarding biopsy.
In the body, PSA is produced by prostate cells and is involved in the liquefaction of semen. While it is normal for men to have some level of PSA in their blood, elevated levels can indicate prostate conditions, including benign prostatic hyperplasia (BPH) or prostate cancer. Free PSA testing provides additional insight into the nature of these elevated levels.
Overall, free PSA is a valuable tool in the evaluation of prostate health and cancer risk. It is often used in conjunction with other assessments to ensure a comprehensive approach to diagnosis and monitoring of prostate conditions.