What is the PSA test?
The most common screening tool for prostate cancer is the prostate-specific antigen (PSA) test. This is a simple blood test that measures the presence of PSA circulating in your bloodstream. This test is usually the first step in any prostate cancer diagnosis. However, the PSA screening by itself cannot tell you if cancer is present.
The PSA test is also used to track the effects of prostate cancer treatment such as surgery, radiation, hormone therapy and chemotherapy. When a man has treatment for prostate cancer, his PSA level will drop significantly. Regular screening with PSA is one of the tools the physician will use to measure if the cancer has returned.
When PSA levels rise to a certain threshold after prostate cancer treatment, this is known as biochemical recurrence. This means that some cancer cells have survived and are producing PSA. If this happens, the doctor will order additional tests and make recommendations for additional treatment.
What is Prostate-Specific Antigen?
PSA is a protein produced by prostate cells, which keeps semen in liquid form so that sperm can swim. A simple blood test can measure how much PSA is present in a man’s bloodstream. When a man has prostate cancer, his PSA level increases, which is why the PSA test is used as a screening tool.
However, the levels of PSA can rise due to a number of reasons, including cancer. When PSA is elevated it is a warning sign that you should follow up on with your doctor.
What is the controversy surrounding PSA screening?
In recent years, there has been some controversy surrounding the PSA test. In 2012, the U.S. Preventive Services Task Force (USPSTF) assigned the PSA test a “D” rating. This meant that the USPSTF concluded the harms that resulted from PSA testing, such as unnecessary biopsies and negative treatment side effects, outweighed the benefits of finding and managing the disease early. This recommendation did not include exceptions for men at increased risk of developing the disease, such as African American men, those with a family history of the disease, and those with BRCA gene mutations. The USPSTF recommendation is important as it guides primary care physicians in preventive care and can impact insurance coverage and reimbursement for screening. Prior to its “D” rating, the PSA test had an “I” rating, meaning the USPSTF concluded there was insufficient evidence to assess the pros and cons of testing.
In response to new research demonstrating the benefits of PSA screening (such as the European Randomized Study of Screening for Prostate Cancer), an increase in the number of men choosing active surveillance, and advocacy efforts, the USPSTF updated their recommendation in April 2017, assigning the PSA test a “C” rating for men ages 55to 69 (the test still has a “D” rating for men ages 70+). This means that the USPSTF recognizes a small potential benefit of PSA testing and recommends that men make individual decisions about whether or not to get tested after discussing the risks and benefits with their doctors. Like the 2012 recommendation, this update does not include specific language for men at increased risk.
The National Comprehensive Cancer Network® (NCCN®) and ZERO – The End of Prostate Cancer strongly recommend that men should be fully educated about prostate cancer, should know their options for early detection, and should have access to the tests we have available now. Researchers, with support from organizations like ZERO, are working every day to improve prostate cancer screening, but for now, we must use the tools we have. A PSA test score is an important part of making a decision on how best to determine a prostate cancer diagnosis and/or treatment pathway. Visit our advocacy site to learn about ZERO’s advocacy efforts in early detection and access to PSA screening.
This 2016 article by Dr. Stacy Loeb provides a thorough overview of the evidence for and against the PSA test, and how we can interpret this evidence with nuance in order to prevent suffering and death.
When should I get a PSA test?
The guidelines below are adapted from the NCCN Clinical Practice Guidelines In Oncology (NCCN Guidelines®) for Prostate Cancer Early Detection. Please use these guidelines to have a discussion with your physician about your personal risk and make a plan for screening.
- Age 40: Talk to your physician about screening and your personal risk
- Age 45-49: Have a baseline PSA and DRE. If PSA above 1 ng/mL, repeat at 1-2 year intervals until age 50. If PSA below 1 ng/mL repeat PSA at age 50.
- Age 50-70: If PSA is below 3ng/mL, repeat screening at 1-2 year intervals
- Age 70 and over: Talk with physician and assess general health to decide together if routine PSA screening should continue.
How can I get a PSA test?
Talk to your general practitioner or urologist about receiving a PSA test in their office. If you do not have insurance or if your insurance does not cover the PSA screening, consult our national free testing map or look into our free testing partners.
Understanding Your PSA Test
In general, a PSA level that is above 4.0 ng/mL is considered suspicious. However, there are many other factors to consider before taking further action. The following are some general PSA level guidelines:
- 0 to 2.5 ng/mL is considered safe
- 2.6 to 4 ng/mL is safe in most men but talk with your doctor about other risk factors
- 4.0 to 10.0 ng/mL is suspicious and might suggest the possibility of prostate cancer. It is associated with a 25% chance of having prostate cancer.
- 10.0 ng/mL and above is dangerous and should be discussed with your doctor immediately. It is associated with a 50% chance of having prostate cancer.
However, PSA levels can easily rise with greater age. You and your physician should consult age-specific normal PSA ranges.
If Your PSA is High
You and your doctor can explore several options if your PSA is high. One option is to have a second PSA screening; recent research has shown that a second screening can improve the accuracy of an abnormal result1. A digital rectal exam (DRE) and a biopsy can also confirm the presence or absence of prostate cancer. However, there are several other reasons why a PSA result might be high:
- Advanced age
- Recent biopsy
- Injury to pelvic region or prostate
- Riding a bicycle
- Sex (within the past 24 hours)
- Supplements that effect testosterone
- Urinary tract infection
If you have an elevated PSA, talk with your doctor about your activities and your health.
If Your PSA is Low
In general, a low PSA is a good result. However, there are several reasons a PSA screening level may be artificially low including taking statins to lower cholesterol, anti-inflammatory drugs and obesity (body fat decreases the amount of PSA circulating in the blood stream). Be sure to discuss these with your doctor.
If Your PSA is Rising Quickly
The rate in yearly increase in the PSA level is known as the PSA velocity. This is one measure of prostate cancer risk, since PSA levels can rise rapidly in men who have prostate cancer. This can be especially useful to find prostate cancer in early stages before the cancer has left the capsule of the prostate.
Research shows that an increase of .75 ng/mL a year is an early indicator of prostate cancer if a man has a total PSA result between 4.0 and 10.0 ng/mL.2 Further, an increase of 2.0 ng/mL over a year period predicts a higher likelihood of death due to aggressive prostate cancer.3
Research is also showing PSA velocity may be able to predict survivability from prostate cancer as men with a PSA increase of .35 ng/ML or less over a year have a 92 percent survival rate compared to PSA increases of more than .35 ng/mL over a year have a 54 percent survival rate.4
The Prostate Health Index was recently approved for the detection of prostate cancer. The PHI is a simple blood test that combines three tests in one. Research has shown that the test is better at detecting prostate cancer than the traditional PSA screening.5 The test also predicts the likelihood of progression during active surveillance.
Because this test is very new, it is possible your physician has not heard of it yet. If you are interested in the test, talk with your doctor and discuss your risk, the test, and how to use the information from the test.