Understanding Your PSA Results

The prostate-specific antigen (PSA) test is routinely used to screen for prostate cancer.

PSA is a specialized protein naturally produced by the prostate gland. If there is any abnormality or infection of the gland, the resulting inflammation will trigger the release of additional PSA. This protein is also produced by prostate cancer cells—the more cancer cells, the higher the PSA level.

Prostate cancer is just one of the conditions the PSA test can help diagnose. While a high PSA may be suggestive of a malignancy, the test alone cannot offer a diagnosis. Other lab tests and evaluations would be needed.

Noncancerous Causes of a High PSA

The PSA test was originally approved by the U.S. Food and Drug Administration in 1986 to monitor the progression of prostate cancer in men diagnosed with the disease. By 1994, it was clear that the test also had value in detecting prostatic inflammation in otherwise symptom-free men.

While prostate cancer is the main focus reason for this test, other noncancerous conditions can also cause the PSA to rise. The most common of these is prostatitis (inflammation of the prostate gland).

Prostatitis is, in fact, the most common cause of prostate problems in men under 50 and can take several forms:

• Acute bacterial prostatitis, most often caused when bacteria leaks from the urinary tract into the prostate gland
• Chronic bacterial prostatitis, characterized by persistent inflammation
• Chronic non-specific prostatitis, for which there may be symptoms but no known cause
• Chronic asymptomatic prostatitis, for which inflammation is present but with no symptoms

Another cause for elevated PSA levels is benign prostatic hyperplasia (BPH), a condition by which the gland itself becomes enlarged. BPH is primarily seen in older men and may cause uncomfortable urinary symptoms, including the impairment of the urinary flow and urinary retention. While it isn't entirely clear what causes BPH, many believe it to be related to changes in sex hormones as men get older.

BPH is neither cancerous nor indicative of cancer. However, it is important to get a diagnosis and treatment for this condition because it can lead to complications such as urinary tract infections (UTIs), bladder stones, bladder damage, and kidney damage.

Placement of a foley catheter can result in temporary false elevation of PSA. In addition, sexual intercourse/ejaculation can also transiently raise PSA.

Detecting Prostate Cancer

In the past, doctors typically considered PSA levels of 4.0 or below to be normal. If levels were above 4.0, doctors would consider that to be a red flag for cancer and order a biopsy.

In recent years, however, doctors have come to understand that there is no real "normal" PSA value. In fact, men with a low PSA can have prostate cancer, while those with PSAs well above 4.0 could be entirely cancer-free.

As such, current guidelines recommend the use of both a PSA and digital rectal exam (DRE) as part of voluntary prostate cancer screening. The DRE is a physical exam in which a finger is inserted into the rectum to evaluate the size and consistency of the gland. It is performed irrespective of PSA values and can be useful in detecting abnormalities.

Based on the results of the tests, the following would typically occur:

• If the PSA is not elevated and the DRE is normal, the doctor may recommend another screening in a year.
• If the PSA is elevated but there are no symptoms or abnormalities, the doctor may recommend another PSA test to confirm the results. If it is still high, the doctor would likely monitor the condition at regular intervals to watch for any changes.
• If the PSA is high or there is a suspicious lump, the doctor may recommend additional tests, such as a urine test (to test for a UTI), X-rays, transrectal ultrasound, magnetic resonance imaging (MRI), or cystoscopy. If prostate cancer is suspected, a biopsy would be recommended.