Prostate-specific antigen (PSA) is a protein found in semen. PSA helps to keep the semen in its liquid form and is made only by prostate cells. When small amounts of the protein get into the circulation, it can be detected and measured in the blood. High PSA levels in the blood, however, may be a sign of a prostate problem. Certain prostate conditions, including benign prostatic Hyperplasia (BPH) or swelling of the prostate and prostate cancer can cause high levels of PSA in the blood.

The growth of the prostate, as well as the production of PSA itself, is controlled by male hormones. Any treatment that lowers the male hormone, DHT, levels will lead to a drop in PSA blood levels.

How Is PSA Measured?

As with many other routine blood tests, PSA is measured from a small sample of blood. The results are usually reported in ng/ml , shorthand for nanograms per milliliter.

What Is a "Normal" PSA?

There are several different ways to measure PSA. Most physicians think that the "normal range" is between 0.0 and 4.0 ng/ml for most PSA tests. However, the lab's "normal" upper level is simply a cutoff point used to separate men who are less likely to have prostate cancer from those for whom further prostate cancer testing may be appropriate, depending upon the circumstances.

What Causes PSA to Rise?

The level of PSA in the bloodstream may be elevated by conditions that lead to an increase in the number of cells making PSA or by a breakdown of the normal barriers in the prostate that usually prevents PSA from getting into the bloodstream.

The most common condition leading to a high PSA is benign (non-cancerous) enlargement of the prostate, called benign prostatic hyperplasia (BPH). BPH is very common in men over the age of 50 and may lead to a variety of problems including difficulty with urination.

Prostate Cancer causes the breakdown of the normal barriers in the Prostate and allow PSA to enter the blood.

Increases in levels of a potentially harmful male hormone, dihydrotestosterone (DHT) the primary androgen in influencing development of prostate cancer can cause increased production of PSA.

Infection or inflammation in the prostate, called Prostitis may also cause elevation of PSA by damaging the PSA barrier in the prostate which allows the protein entry into the blood stream.

Both BPH and prostate cancer are common in men over the age of 50. In addition, there is a lot of overlap in blood PSA levels between men with BPH and those with early prostate cancer. These factors limit the usefulness of PSA as a tool for detecting curable prostate cancer. Many patients who have a PSA level higher than "4 ng/ml" will eventually be found not to have prostate cancer. If PSA is tested on men with BPH but no prostate cancer, as many as one-third to one-half of such men will have an elevated PSA. Their PSA results, however, are generally in the 4 to 10 ng/ml range.

Repeating PSA tests once every year may be useful to find some of the cancers in men who have a normal PSA at first. PSA testing has led to an increase in the detection of prostate cancer. Only with a biopsy can the diagnosis be made.

What Do My PSA Results Mean?

If your DRE is normal and your PSA blood level is less than "4 ng/ml" (on the most common tests), no further testing usually is needed at this time. Physicians who recommend PSA testing generally suggest that you should have both the DRE and PSA each year. If your PSA is over "4 ng/ml" or your rectal exam shows an area of hardness or firmness in your prostate, most experts would recommend that you have a prostate biopsy.

About one in 20 healthy men who are screened will have prostate cancer detected. If either the PSA or DRE is abnormal, your risk of having prostate cancer increases. Although there is some uncertainty, your overall risk of prostate cancer, based upon the PSA and DRE results, is summarized in the table below.

Determining Chance of Prostate Cancer
(American Foundation for Urological Health)

What can be done to Lower PSA Levels and to Reduce Risk of Cancer?

The American Cancer Society has recommended a PSA test every year in men over the age of 50, or men over 40 with blood relatives who have had prostate cancer, or men who are in high-risk groups, such as African Americans. An annual examination by a physician should also be performed. In addition, a change of diet would be very helpful. Cultures that consume high amounts of cruciferous vegetables show lower incidents of prostate cancer and lower levels of PSA.

Using dietary supplements that will balance hormonal levels can also be effective. Any treatment that lowers male hormone levels will lead to a drop in PSA blood levels. Complete Prostate Nutrition contains materials that may reduce the risk of prostate cancer and control BPH symptoms. Tests have shown that DIM inhibits the actions of dihydrotestosterone (DHT), the primary androgen involved in prostate cancer. DHT stimulates the expression of Prostate Specific Antigen (PSA), which acts as a growth factor for prostate cancer. When androgen-dependent cells were treated with DIM, the researchers found a drop in the level of PSA.