Imperfect prostate cancer test leaves men with scary choice THE PSA PROBLEM

THE PSA TEST

QUESTION: What is PSA?

ANSWER: Prostate Specific Antigen (PSA) is a protein produced by the prostate gland. It can be measured in urine and blood.

Q: Does PSA find cancer?

A: It can, but it also detects elevations of the protein caused by benign prostate diseases, urinary tract and other infections, sexual activity and masturbation.

Q: Should all men get the PSA test?

A: Most doctors feels men should be tested after age 50, though African Americans or those who have a family history should test earlier.

Q: What’s a high PSA score?

A: Doctors used to set the number 4 as the point at which a man needed more tests. Generally, the higher the number, the more likely a man has a prostate problem, though not necessarily cancer.

Q: Are there tests currently available that better pinpoint cancer?

A: Yes, though there’s some debate about how much better they are. Some doctors say the size of the prostate gland itself needs to be measured when a man has a borderline PSA score. There also are refinements of the standard PSA test. One tracks the changes in the PSA level over months. Another measures “free-PSA,” how much PSA winds up in the bloodstream. The lower the free-PSA number, the more likely a man is to have cancer.

By Patricia Anstett

Detroit Free Press

DETROIT

At 74, Roger Watkins had no desire for his doctor to poke around more to find out whether he had prostate cancer.

When a test came back in 2008 suggesting he might have it, Watkins and his urologist, Dr. Muzammil Ahmed, agreed to keep an eye on his prostate specific antigen (PSA) scores in the months ahead but to “leave well enough alone.”

Further examination showed that Watkins may have gotten an elevated score for other reasons, including his age and the size of his prostate. Tests this year showed that Watkins’ PSA score had dropped — from 4.2 in 2008 to a safer 2.9.

“I don’t believe in rushing into anything,” said Watkins, a retired General Dynamics business process specialist who lives in Northville, Mich., with Marcia, his wife of 51 years.

Across the nation, men like Watkins are talking to their doctors about the latest controversy over PSA testing, particularly because new, more promising tests might be close to federal approval, perhaps just a year or two away.

The traditional PSA test, developed in 1991 by Dr. William Catalona, a Northwestern University urologist, has always been controversial because high scores often don’t mean prostate cancer. A federal advisory committee this month said it could not recommend the test because it leads to unnecessary biopsies, surgery and other treatments that can cause death or permanent disabilities, such as incontinence.

The new tests promise to better identify men with prostate cancer, particularly an aggressive form of it.

A University of Michigan team, headed by Dr. Arul Cinnaiyan, is working with GenProbe, a San Diego molecular diagnostics testing firm, to develop a single test that finds two biomarkers of prostate cancer.

One of the biomarkers is a gene that fuses with others “that we believe is the one driving the disease,” Cinnaiyan said. The other biomarker is associated with more aggressive prostate cancer.

Cinnaiyan said he hopes the test will be more widely available next year through a national study. Doctors would be able to mail urine samples for analysis, he said. The test would be a complement, not a replacement, for the PSA test and a digital rectal exam.

Another blood test, developed by Catalona, looks for a more specific antigen produced by prostate cancer cells.

This Pro-PSA score is factored into a formula to create a score of a man’s prostate health. The higher the number, the higher likelihood a man has cancer. That should let doctors know whether a biopsy is needed, Catalona said.

His test, now in development by the Beckman Coulter biomedical testing firm of Brea, Calif., awaits federal approval. It’s already available in Europe and Australia.

Until federal approval, men have to sort out their choices.

“We tell our patients — that screening should begin at 40 or 45 and after that, probably once a year is enough, unless the PSA changes by 0.5 in one year,” said Dr. Kenneth Kernen, director of urology at Beaumont Hospital, Royal Oak.

Dr. Isaac Powell, a Karmanos Cancer Institute urologist, believes the test is particularly important for U.S. black men, who are more than twice as likely to die from the cancer as white men. “As a prostate cancer survivor, I take an aggressive approach” with black men and others with a family history of prostate cancer, he said.