Prostate-Specific Antigen (PSA), Free:Total Ratio

What is the prostate and prostate-specific antigen?

The prostate is a small gland of the reproductive system of men. Having the shape and size of a walnut, this gland is located below the bladder in front of the rectum. The prostate surrounds the urethra, which is the tube that carries the pee to the outside from the bladder. It helps in the production of the semen fluid that can carry sperm from a man’s testicles to the outside through ejaculation. As a part of aging, this gland tends to increase in size to reach the size of an apricot by the time a man is in his forties; and, the size of a lemon by the time he is in his sixties. When the prostate gland enlarges, as a part of natural process of life, it squeezes on the urethra leading to problems in the urinary tract. These problems normally occur in men by the time they are in their fifties.

Such an enlargement of the prostate gland is benign and refereed to as a benign prostatic hyperplasia, otherwise known as BPH. This process cannot be prevented and is highly dependent on age and genetics. Studies show that 8 out of every 10 men will develop BPH; and, 90% of men who are aged 85 and above have BPH. Out of all these cases, only 30% will be bothered by the accompanied symptoms of this condition. Signs include a bladder that doesn’t empty even after peeing, the sudden urge to pee, an interrupted flow of urine, and the need to make an effort to urinate. While such an enlargement is benign, when the enlarged prostate gland is left untreated, it may lead to damages to the kidneys and bladder.

Prostatitis is another condition of this gland that consists of the inflammation of the prostate. This condition, unlike BPH, can affect men at any age. Men at young as teenagers can be affected. Its symptoms include having some trouble urinating, feeling chills and developing a fever, as well as having sexual problems. This condition is normally treated with a course of antibiotics.

Prostate cancer is yet another type of illness that can affect the prostate gland. This condition is the most common form of cancer among American men and one of the leading causes of death. According to the American Cancer Society, 174,650 new cases of prostate cancer appeared in the United States in 2019. Among them, 31,620 men died. It is assumed that one in 9 men will be diagnosed with prostate cancer within their lifetime; and, one in 41 will die from it.

The PSA test is a blood test that is used to screen for prostate health including the enlargement of the gland, its inflammation or prostate cancer. This test measures the levels of a protein called the PSA, prostate-specific antigen. This protein is found in men’s semen as it is produced and released by the prostate gland. So, PSA is found in the semen; but, a small amount escapes into the bloodstream. A healthy man has small amounts of this protein circulating in the blood. Higher than normal levels can indicate any of the above-mentioned prostate conditions. When the man has an inflammation, enlargement or even cancer cells in the prostate, PSA levels tend to increase.

PSA proteins are found in small amounts; so, their detection is very delicate and requires a sensitive technology. This protein is found in two forms. The first form is the free PSA that circulates in the blood freely. The second type is the bound or complexed PSA that is normally bound to either one of these three substances: alpha-2-macroglobulin, alpha 1-antichymotrypsin, and albumin. The total level of PSA is the combination of both free and bound forms of PSA.

Why get tested for PSA Free: Total?

You need to get tested for PSA to diagnose prostate cancer (both symptomatic and asymptomatic), help determining if a biopsy is needed and to monitor how effective the chosen treatment is. This test can also help detect whether prostate cancer may be recurring. This PSA test can also detect prostate enlargement and prostatitis. Under certain circumstances, more tests are required to have a better diagnosis, such as a urinalysis or imaging tests.

The PSA test is a part of a health screening for men. The American Cancer Society asks men who are healthy, in general, to get tested yearly by the time they turn 50 years. From another angle, the American Urological Association advises men between the ages of 55 and 69 to routinely check their PSA levels. No routine screening is recommended by the time a man is 70 years old.

Men who have symptoms of prostate cancer need to get tested. These symptoms include having difficult, painful and frequent urination, back pain and pelvic pain. For those who had high levels of PSA, the test needs to be retaken in a few weeks to check if the levels may go back to normal.

What can affect the levels of PSA?

You need to pay attention to many factors before taking the PSA test. DRE and prostate manipulation biopsies will elevate your PSA levels. Also, working out rigorously can lead to higher rates. But, such a rise is temporary. From another angle, men who ejaculate within the past 24 hours of taking the test may have temporary high levels of PSA.

Some chemotherapeutic drugs, like cyclophosphamide and methotrexate, can alter your PSA levels. High levels are normally monitored; and, the test has to be repeated within 3 to 8 weeks after the first test before any further action is taken. However, if your doctor may suspect inflammation of the prostate, a course of antibiotics may be given.

What your PSA Free and Total test results mean?

These are the normal ranges of PSA for men of different age groups and ethnicity. Between the ages of 40 and 49, Free PSA values need to be between 0 and 2 ng/ml for Asian Americans and African Americans; and, between 0 and 2.5 ng/ml for Caucasians. Between the ages of 50 and 59, PSA values need to be between 0 and 3 ng/ml for Asian Americans, between 0 and 4ng/ml for African Americans; and, between 0 and 3.5 ng/ml for Caucasians. Between the ages of 60 and 69, PSA values need to be between 0 and 4ng/ml for Asian Americans, 0 and 4.5 ng/ml for African Americans and Caucasians.

The free to total ratio test calculated the percentage of free PSA proteins to the total number of PSA. According to this percentage, you will know your risk for developing prostate cancer.

• If your free to total PSA percentage is between 0 and 10: you are 56% likely to develop prostate cancer if you are between the ages of 50 and 64; and, 55% more likely if you were between ages 65 and 75.
• If your free to total PSA percentage is between 10.01 and 15: you are 24% likely to develop prostate cancer if you are between the ages of 50 and 64; and, 35% more likely if you were between ages 65 and 75.
• If your free to total PSA percentage is between 15.01 and 20: you are 17% more likely to develop prostate cancer if you are between the ages of 50 and 64; and, 23% more likely if you were between ages 65 and 75.
• If your free to total PSA percentage is between 20.01 and 25: you are 10% more likely to develop prostate cancer if you are between the ages of 50 and 64; and, 20% more likely if you were between ages 65 and 75.
• If your free to total PSA percentage is above 25%: you are 5% more likely to develop prostate cancer if you are between the ages of 50 and 64; and, 9% more likely if you were between ages 65 and 75.

Interpreting your PSA results may be delicate. Sometimes, your health care provider may investigate numerous factors associated with PSA levels. These include PSA velocity: how your PSA are changing with time and whether there is a rapid rise; the percentage of free PSA: which is the ratio between free and total PSA levels; and PSA density: which is the amount of produced PSA per volume of tissue.

Whatever your test results are, your doctor needs to investigate further your numbers and their variations to have the most accurate diagnosis. According to his findings, treatments are chosen.

Where can I get a PSA Free and Total test near me?

Please use our Lab Locator to find find a convenient testing location.

NOTE: PSA tests are available through Health Testing Centers for men age 40 and older. If you are younger than 40 and interested in PSA testing, contact your primary care doctor or urologist.

Reviewed By: Dr. Kurt Kloss, MD
Last Reviewed Date: Mar 25, 2020