PSA Test
Overview
The PSA test checks the amount of prostate-specific antigen (PSA) in a person’s The PSA test checks the amount of prostate-specific antigen (PSA) in a person’s blood. The prostate gland, found just below the bladder in men, makes PSA.
While most PSA stays in semen, some naturally moves into the bloodstream. Doctors often use this test to look for signs of prostate cancer, but high PSA results do not always mean cancer. Many factors can lead to higher PSA levels, such as:
- Prostate gland enlargement
- Inflammation or infection
- Recent medical procedures
PSA test results can sometimes be confusing, so doctors may use them alongside other tests and details about a person’s health. Men often talk with their healthcare provider about the pros and cons of testing to make the best choice for their situation.
Reasons for Performing the PSA Test
Doctors mainly use the PSA test to help find early signs of prostate problems, including cancer. While high PSA levels can be a sign of cancer, other noncancerous conditions may also cause PSA to rise.
The PSA test is often combined with a digital rectal exam to improve screening accuracy. These screenings can suggest whether there are changes or growths in the prostate. Here is a sample comparison of screening tools:
| Screening Tool | Checks For |
|---|---|
| PSA Blood Test | Raised PSA levels |
| Digital Rectal Exam | Lumps or hard spots on prostate |
If both the PSA test and rectal exam show irregular results, doctors may recommend a biopsy. This tissue test can confirm if cancer cells are present.
Additional Uses for PSA Testing
Beyond initial screening, doctors use the PSA test in other situations. People who already have prostate cancer usually get this test to see if treatments are working.
Doctors track PSA levels over time to look for any rising numbers, which can mean that the cancer has come back or is growing again. In these ways, the test helps guide choices about more treatment or closer monitoring.
Possible Concerns
Positive Aspects of the PSA Test
The PSA test can help find prostate cancer before any symptoms appear. Early detection may make treatment easier and lower the chance that the cancer spreads. Some people who have cancer found early might live longer because they start treatment sooner.
Not all prostate cancers grow quickly—many grow so slowly that they may not need treatment. For some men, knowing about prostate cancer early can provide more options and peace of mind, even if immediate treatment isn’t necessary.
Drawbacks and Challenges of the PSA Test
The PSA test is not perfect. Someone can have a high PSA without having cancer, while someone else might have cancer even when their PSA is not elevated. This means the test can sometimes miss cancer (a false negative) or suggest cancer when there is none (a false positive).
Many non-cancerous conditions can also raise PSA levels, such as benign prostatic hyperplasia (BPH)—an enlarged prostate—and prostate infections. PSA levels also tend to rise naturally with age.
On the other hand, certain medications, including those used to treat BPH or some chemotherapy drugs, can lower PSA levels. Being overweight may also reduce PSA numbers. These factors can sometimes hide the presence of cancer and make the test less reliable.
Another concern is overdiagnosis. Some prostate cancers found through PSA testing may never cause health problems. However, discovering them can lead to unnecessary worry, follow-up tests, or treatments that may not be needed.
Biopsy Risks
When PSA levels are elevated, doctors may recommend further procedures, such as a prostate biopsy, to learn more. While a biopsy can help confirm a diagnosis, it also carries certain risks, including pain, bleeding, or infection. These side effects can be uncomfortable and may cause concern, especially when the biopsy reveals a condition that would not have caused harm.
What to Expect During the Screening
A health professional uses a needle to collect a blood sample from the arm for the PSA test. The sample is then sent to a laboratory for analysis.
The results help screen for prostate cancer and are often used together with a digital rectal exam. Both tests are quick and typically take only a few minutes to perform in a clinical setting.
Test Outcomes
Different Approaches to PSA Testing
Doctors measure PSA test results in nanograms per milliliter (ng/mL). Test interpretation is not always clear-cut, as no universal value defines a “normal” PSA level for everyone. Several methods exist to help better understand what the numbers may mean:
| Test Variation | What It Measures | How It Is Used |
|---|---|---|
| PSA Change Rate | How much the PSA level rises or falls over time. | A quick increase might suggest a heightened cancer risk. |
| Free PSA Percent | How much PSA is not attached to proteins in the blood. | A lower percentage may signal a higher cancer chance. |
| PSA Density | The PSA level adjusted for prostate size. | Higher density might indicate more cancer activity. |
Some patients with a family history of prostate cancer or those older in age may face a higher risk, making these test variations especially important in certain situations.
Researchers continue to study if some of these methods offer more accurate screening or better guidance for patients. A normal PSA level can be different based on age and individual health.
For example, many healthy adults have PSA below 4.0 ng/mL, but higher numbers, especially over 10 ng/mL, raise concern for cancer. The benefits of prostate cancer screening may be greater for people with a family history or risk factors.
Discuss Results With Your Health Care Provider
Patients should talk openly with a doctor before deciding about PSA testing. They should ask about the possible benefits, such as early detection, as well as any risks linked to false positives or unnecessary tests. Questions to consider include:
- When and how results will be shared
- Steps to take if elevated PSA or abnormal results occur
- The schedule for future screening if no issues are found
Older adults or those with a family history may need to weigh the pros and cons more carefully with their doctor. Being informed about test options and results can make it easier to manage health choices.
