Prostate-specific antigen (PSA) is a protein which is produced by the cells of the prostate gland. Elevated levels of PSA might indicate a non-cancerous condition such as prostatitis, prostate cancer or an enlarged prostate. The PSA levels may tend to increase in all men as they age up. The PSA test measures PSA level in a man’s blood. For PSA test, a sample of blood is collected from the patient and is sent to a lab for examination. The result of the tests is usually reported as nanograms of PSA per milliliter of blood. PSA exists in the blood in two main forms that are complexed and free. Total PSA is the most frequently used test which helps in measuring the sum of complexed and free PSA in the blood.
