PSA test still an important part of prostate cancer arsenal


Controversy surrounding a common screening tool for prostate cancer has left many men wondering whether it’s worth it to take the test.
Prostate-specific antigen (PSA) is a substance released into the blood by the prostate gland. A PSA blood test measures the amount of the substance in the blood. Because a high PSA level has been thought to indicate possible cancer, the next step often is a biopsy.

The test, together with a digital rectal exam, is a recommended part of the annual physical for men 50 and over.

For those at higher risk, including family history of the disease or African American descent, screenings begin at age 40.
The controversy is whether or not the PSA test is the “gold standard” it was once thought to be.

According to Mills-Peninsula’s chief urology specialist, the controversy has merit, but the PSA test shouldn’t be discounted.

“There’s little doubt that PSA does not reflect cancer all the time,” John Connolly, M.D., said. “The amount of PSA increases normally as a man’s prostate enlarges with age, and there are other causes.

“The most common is a condition called Benign Prostatic Hyperplasia (BPH),” he said. “Others include prostate infection or trauma, urinary infection and even some herbal supplements.”

To further confuse the issue, about 20 percent of men with prostate cancer never develop high PSA levels, while about two-thirds who test high turn out to be cancer free.

The key, Dr. Connolly said, is to use the test as a first step in a comprehensive diagnostic process.

“Mills-Peninsula urologists believe the PSA test is still a good tool,” he said, “but it has to be used judiciously. “In addition to total PSA antigen levels, we look at PSA as it relates to prostate volume and rate of change from year to year.

“More refined antigen evaluations also are important, including density and, in men with PSA levels between 2 1/2 and 10, measurement of free versus total PSA. In a normal test, the free PSA should be above 20-25 percent of the total.

“PSA testing is especially helpful in early diagnosis,” Dr. Connolly said. “Prior to PSA, only 25 percent of prostate cancers were found while still confined to the gland. With PSA, about 80 percent are confined or just locally advanced.

“We look at the whole person,” the doctor said. “Age, family history, general health and digital rectal exam findings all go into the overall assessment.

“Prostate cancer is still the second leading cause of cancer death in men, right behind lung cancer,” Dr. Connolly said. “The PSA test may not be perfect, but it’s an important part of our arsenal.”