PSA Levels and What They Mean

PSA stands for prostate specific antigen, which is a type of protein produced by the prostate gland. A small quantity of this protein can be found in blood serum of all healthy men, though an elevated level is considered to be an indicator of certain health problems. A significantly high level of PSA in blood is sometimes considered as an indicator of diseases like, benign prostatic hyperplasia (BPH) and prostate cancer. PSA test is basically performed for the early detection of prostate cancer. However, a high level of PSA alone is not sufficient for a confirmed diagnosis of prostate cancer, for which a positive PSA test is sometimes followed by digital rectal exam (DRE) and biopsy. Moreover, a high PSA level can also be associated with other benign or non cancerous conditions.

Possible Causes of High PSA Levels

A high PSA level can mean several different things. A high level of PSA in the body may or may not be associated with cancer of the prostate gland. More commonly, it can be associated with some non cancerous conditions like, enlarged prostate or BPH, which is quite common among the elderly. Unlike cancer, it does not spread to any other parts of the body. Other than BPH, it could be an indicator of prostatitis or inflammation of the prostate gland.

Prostatitis can be caused by bacterial infection along with some other factors. Apart from the various health problems, a slight increase in PSA can be observed in men who have recently undergone prostate biopsy and digital rectal exam. Even recent ejaculation and bicycle riding can cause PSA level to rise slightly. Intake of certain medications can also affect the level of PSA. Therefore, one should disclose all information pertaining to the use of medications to their physician before the test, in order to ensure a proper evaluation of prostate health.

PSA Levels and their Meaning

The level of PSA is measured in nanograms per millimeter of blood. Usually, it is considered that a value under 4 ng/ml is normal. On the other hand, a value falling in the range of 4 to 10 ng/ml is considered to indicate a 25% chance of prostate cancer, according to American Cancer Society. PSA levels between 4 to 10 ng/ml can also indicate prostatitis and benign prostatic hyperplasia or BPH. A value higher than 10 ng/ml is regarded as an indicator of increased risk for getting cancer of the prostate. However, the answer to 'what does high PSA levels mean' is not so simple, as it appears. In fact, it has been observed that results of PSA tests can fluctuate significantly. In a study, about 15% of the men with PSA level at or less than 4 ng/ml were diagnosed to have prostate cancer. Again, in another study, only 25 to 35% of men with high PSA levels were found to have prostate cancer.

Thus, lots of controversies exist regarding the normal level of PSA. Even factors like, inflammation and ejaculation within two days of having a PSA test can cause the PSA level in the body to rise slightly. Moreover, the PSA level in the body usually rises with growing age, which leads to the formulation of age-adjusted PSA. According to age-adjusted PSA, a value less than 2.4 ng/ml is normal for men under the age of 50 years, while 3 ng/ml or less is the normal range for a man under the age of 60 years. A value equal to or less than 4 ng/ml is the normal range for a man in the age group of 60 to 69 years. On the other hand, if a man aged over 70 years is found to have 5 ng/ml or less PSA in the blood, then it is considered as normal.

In addition to the value of PSA, PSA velocity and PSA density are two other factors which are taken into consideration while performing this screening test. PSA velocity refers to the change in PSA concentration over time, while PSA density is the comparison of PSA concentration to the volume of the prostate gland. Measuring PSA density is important as PSA level is usually higher in a man with larger prostate gland. PSA test has been approved by the Food and Drug Administration of United States to help the detection of prostate cancer in men aged 50 years or more. This test has also been approved to monitor the patients with a history of prostate cancer, in order to detect recurrences.

Sometimes, high level of PSA may indicate only non cancerous enlargement of the prostate. At the same time, low level of prostate specific antigen also does not rule out the possibility of cancer. To sum up, this test is not perfect, as it is prone to 'false positives' and 'false negative' test results. A false positive test (a high level of PSA in the absence of cancer) is usually followed by other diagnostic tests, which can not only be costly, but can carry certain potential risks for the individual as well. On the other hand, 'false negative' results may show PSA to be in the normal range, even when cancer is actually present. However, this test can still help many people to ensure an early diagnosis of prostate cancer.