A PSA test is usually done to screen men for prostate cancer. Prostate cancer is the second leading cause of cancer deaths in men following lung cancer. It is also the most common non-skin cancer found in men. Although PSA tests can be controversial because there is a lack of evidence that screening prevents deaths from prostate cancer, but it can be a vital tool for a man’s health and well-being. This article explains the normal PSA levels and what to do if you have a high PSA level.
Why Is a PSA Test Done?
The PSA test measures the blood level of PSA (prostate-specific antigen). PSA is a protein that the prostate gland manufactures. If a man has high PSA levels, it is likely he has prostate cancer. But there are other factors for a man with a high PSA level aside from prostate cancer. For example, the man could have an inflamed or swollen bladder. Conversely, a man with high PSA levels may not have prostate cancer.
In addition to screening for prostate cancer, PSA tests are used on men with prostate cancer to determine if their cancer is responding to therapy or has returned. PSA is found in semen and in a man’s blood in small amounts. A PSA test uses a blood sample taken from a man’s vein from his arm usually. The blood sample is then examined in a medical lab to determine the PSA levels.
PSA Levels
Usually, the prostate gland increases in size and produces more PSA as men age. It is normal to have low PSA levels in young men and high PSA levels in older men. A normal PSA serum has a concentration range between 1.0 and 4.0 ng/mL (nanograms of PSA per milliliter). In general, PSA levels greater than 4 ng/mL are considered a risk factor for cancer. Heredity and ethnicity also are a factor in PSA levels. In addition to the single PSA reading, the yearly changes in PSA numbers (PSA-velocity) help determine a normal level.
Age-specific Serum PSA Range:
As mentioned earlier, the prostate naturally produces more PSA as men age – so the older a man is usually the higher the PSA level is. PSA levels have been conducted primarily in populations of white men but African-Americans are more likely to be diagnosed with prostate cancer. There is no clear consensus in the medical field recommending a set PSA threshold for a prostate biopsy for men of any ethnic group. Although controversial, the practice of adjusting the PSA reading cutoff levels based on a man’s age and PSA production has helped to stop needless prostate biopsies in older men. Below are the PSA reading cutoff levels for age and race.
| Age Range (Years) | African Americans | Asian Americans | Caucasians |
|---|---|---|---|
| 40 to 49 |
0 to 2.0 ng/mL |
0 to 2.0 ng/mL |
0 to 2.5 ng/mL |
| 50 to 59 |
0 to 4.0 ng/mL |
0 to 3.0 ng/mL |
0 to 3.5 ng/mL |
| 60 to 69 |
0 to 4.5 ng/mL |
0 to 4.0 ng/mL |
0 to 4.5 ng/mL |
| 70 to 79 |
0 to 5.5 ng/mL |
0 to 5.0 ng/mL |
0 to 6.5 ng/mL |
What If You Have an Elevated PSA Level
A high PSA level could mean a man has prostate cancer, but two out of three men with high PSA levels do not have prostate cancer. Other factors aside from ethnicity and age affect a PSA level. These factors include:
- An enlarged bladder unable to pass urine
- Urine infection
- Noncancerous enlargement of the prostate
- Acute prostatitis – a bacterial infection in the prostate gland
If a man has a high PSA level, the doctor may request another PSA test. If that PSA test shows a high PSA level, the doctor may recommend that the man continue with PSA tests and digital rectal exams (DRE) at regular intervals to watch for changes over time. If it is suspected a man has prostate cancer, a prostate biopsy is performed.
Limitations and Risks of PSA Test
PSA tests have met with controversy in some medical circles. A PSA test can detect prostate cancer, but there are limitations to the test. As discussed earlier, age and conditions such as an enlarged bladder and prostatitis can raise PSA levels. Other limitations of a PSA test include:
- Drugs may lower a PSA reading. For example, drugs used to treat an enlarged prostate have caused low PSA readings.
- Results of a PSA test can be misleading. A high PSA reading does not mean a man has prostate cancer and a low PSA reading does not guarantee a man is free of prostate cancer.
- Overdiagnosis is another limitation of PSA test. Various medical studies have shown that 17 to 50 percent of men who have cancerous tumors discovered in their prostates will not develop life-threatening condition in their natural lifespan. Overdiagnosis can lead to unnecessary surgery and radiation treatments for a man.
- PSA tests have been known to give false-positive results (high PSA level with no cancer) causing great anxiety for a man.
The risk factors involved in PSA tests are how a man decides to use his PSA test results and undergo prostate cancer treatments. For instance, if the results are high he might have a prostate biopsy that carries its own risk of pain and possible infection. If a man is diagnosed with prostate cancer, and it appears to be a slow-growing tumor that is not life threatening, he could experience severe anxiety knowing he has a tumor.