PSA (prostate-specific antigen) testing at a glance
- PSA testing is a blood test for men that assesses levels of the prostate-specific antigen, a protein that can indicate the presence of prostate cancer.
- The PSA test has saved many lives due to early diagnosis of prostate cancer, the second leading cancer-related cause of death in men.
- Guidelines for when to give PSA tests are subject to debate, but general advice is that anyone considering a PSA test should know all the benefits, limitations and risks before proceeding.
- Urology Associates recommends men age 55-69 discuss PSA testing with their physician, as should men 40-54 who are at higher risk for prostate cancer.
What is a PSA test?
The PSA (prostate-specific antigen) test, also called PSA screening, evaluates a blood sample for elevated levels of the prostate-specific antigen. PSA is a protein that can indicate the presence of cancer in the prostate, which is a small gland below the bladder. The PSA test has saved many lives because of early detection of prostate cancer, the second leading cause of cancer-related death in men after lung cancer.
Prior to the 1994 Food and Drug Administration approval of the PSA test, diagnoses of prostate cancer were most often made at a late stage in the cancer’s progression, resulting in a low 5 percent cure rate. That cure rate today, due in part to PSA testing, is 80-90 percent. About 1 in 6 men will have prostate cancer but only 1 in 35 will die from it, thanks to early diagnosis and increased awareness of the issue.
A digital rectum exam (DRE), which is often conducted in conjunction with a PSA test, is another means of testing a man for prostate cancer. In a DRE, the doctor feels the prostate and evaluates for lumps or hard areas that could indicate prostate cancer.
A PSA test is relatively simple. A small blood sample is sent to a laboratory and the results are reported in a ratio of nanograms of PSA for every milliliter of blood. The higher the PSA levels, the more likely a man has prostate cancer. PSA levels below 4.0 ng/mL are generally considered normal. If a PSA exam comes back high, a biopsy of cells from the prostate will be taken to confirm whether or not the patient has prostate cancer.
Other conditions such as an inflamed prostate, can also result in high levels of PSA.
Related blog: Do I Really Need a PSA Test?
What are the risk factors for prostate cancer?
Men at higher risk for developing prostate cancer are candidates for PSA testing. Risk factors include:
- Men under 40 rarely get prostate cancer but the risk rises steadily after age 50.
- African-Americans and Caribbean men of African descent are more likely to have prostate cancer than any other race. Hispanic/Latino and Asian-American men are less likely to get prostate cancer than others.
- Geographic area. North America, the Caribbean, northwest Europe and Australia have more cases of prostate cancer than other areas, and it is less common in South America, Central America, Asia and Africa.
- Having a brother or father who has had prostate cancer more than doubles a man’s chance of getting it. The more family members who have had it, the more the risk.
- Gene changes. Men with Lynch syndrome and those with BRCA1 and BRCA2 mutations account for a small number of cases.
Other factors such as diet, obesity, smoking and toxin exposure are under study, with no positive links determined at this time.
Who should get a PSA test & when?
Controversy over when to give a PSA test began in 2011 when the United States Preventive Service Task Force (USPSTF) recommended reducing PSA screenings for men. This task force was comprised of 16 volunteer clinicians but no urologists were directly involved in the recommendation, which was to only conduct PSA tests when symptoms of prostate cancer are present.
Urology Associates believes that this recommendation is a disservice to all men. Prostate cancer is often slow growing and it is usually in its later stages when men start experiencing symptoms. Waiting until symptoms appear to do a PSA test risks missing diagnosis at an early stage, a large factor in successful treatment of prostate cancer. We also recommend that all men, no matter their risk of prostate cancer, should be under the treatment of a urologist, not a primary care provider, when it comes to prostate health.
Urology Associates and The American Urological Association (AUA) say that no one should ever receive a PSA test until he has a clear understanding of the facts, limitations, benefits and risks of the PSA test. Men should speak with their urologist about the PSA test and whether it is suitable for them.
Data evaluated by the AUA shows that in men age 55-69 who have a PSA test, 1 in 1,000 will avert death by prostate cancer over a decade, with the benefit over a lifetime likely much greater. Due to the side effects of prostate cancer treatment, such as urinary incontinence, bowel problems and sexual dysfunction (not having an erection sufficient for sexual intercourse), the benefit of the PSA test must be weighed against the risks from treatment.
Our PSA testing guidelines
- Men age 55-69 at average risk for prostate cancer should consider PSA testing after consultation with their urologist.
- For these men who decide to get a PSA test, it is generally recommended that they do so every other year, because that interval preserves the majority of the screening benefit while reducing the risks of false positives and overdiagnosis (see below).
- In general, PSA tests should not be administered to men under age 40.
- Men age 40-54 at average risk for prostate cancer should not be tested for PSA.
- Men older than 70 or with a life expectancy of less than 10-15 years shouldn’t have a PSA test, because their detected prostate cancer in those situations is not likely to be treated.
- Men at high risk of prostate cancer should receive PSA testing at their and their urologists’ discretion.
- A PSA test is often given to men who have already been diagnosed with prostate cancer to indicate if/when treatments should begin, to evaluate the effectiveness of treatment, and to detect if prostate cancer has returned after treatment.
What are the risks and limitations of a PSA test?
The actual test, which is a blood draw, has virtually no risks. But the PSA test may return false-positive results, meaning it indicates the presence of prostate cancer when it is actually not present. Similarly, it can give false-negatives, suggesting prostate cancer is not present when it actually is. Of the men who have a biopsy due to high PSA levels, only about 25 percent actually have prostate cancer.
A more thorny issue involves whether prostate cancer detected through a PSA test should be treated. PSA tests can detect small cancer tumors that cause no symptoms. Many prostate cancer tumors grow so slowly that they don’t threaten the man’s life. Detecting such small tumors is often called “overdiagnosis,” and treating such tumors is called “overtreatment.”
Since treatments such as radiation, chemotherapy and surgery often carry problematic side effects, “overtreatment” can result in men experiencing these side effects unnecessarily.