Sunday, March 18, 2012

Study finds PSA testing cuts prostate cancer death risk, but does it save lives?

Study finds PSA testing cuts prostate cancer death risk


Countering other reports, researchers found the screen reduced mortality rate by 30 percent.

18 march 2012-- Adding another perspective to one of the most controversial and confounding issues in medicine, a new European study reports that men who received routine prostate-specific antigen (PSA) tests to check for signs of prostate cancer were 30 percent less likely to die from the disease.

But the big picture isn't simple enough for the new research to solve once and for all the question of whether PSA testing helps men.

"There is little doubt that a man who undergoes testing will have about a 30 percent less chance of dying from prostate cancer," said the study's lead author, Dr. Fritz Schroder, professor of urology at Erasmus University in Rotterdam, Netherlands. "On the other side, there's a 30 percent chance that a cancer found is insignificant and the patient may be confronted with the side effects of treatment unnecessarily."

Schroder is referring to the major issue in the PSA debate: Do the PSA tests do more harm than good?

In some cases, the tests detect cancer that would be deadly, giving men an opportunity to treat it and potentially survive. In other cases, men are unnecessarily treated for cancer that actually would develop so slowly that it wouldn't threaten their lives.

There's also the matter of cost -- PSA screenings cost an estimated $3 billion in the United States each year -- and the potentially severe side effects of treatment, including incontinence and impotence. In addition, the new study found that only about 0.5 percent of men developed the cancer and died from it in the period reviewed.

For the new study, the scientists examined the medical records of more than 160,000 men in eight European countries, who ranged in age from 55 to 69 when the study began. Some were randomly assigned to receive PSA screening tests.

After an average of 11 years, the men in the study who got screened were 21 percent less likely to have died from prostate cancer.

The study findings appear in the March 15 issue of the New England Journal of Medicine.

A physician who wrote an accompanying journal commentary said the new findings "add more confusion" to the issue. But one thing is clear: They don't convince him that routine PSA tests are a good idea.

The problem is that "you can have prostate cancer sitting there, doing nothing," said Dr. Anthony Miller, professor emeritus of epidemiology at the University of Toronto's Dalla Lana School of Public Health. "It's not going to kill them; it's not going to grow."

But a PSA test can still discover prostate cancer, leading to unnecessary tests and treatment.

"You'll always find people who are convinced that no matter what is done, the evidence doesn't matter and what they really want to find out is if they have any cancer," Miller said. "They will assume that the mere fact of finding a cancer will mean that good has been done."

Miller recommends the PSA test only for men who have certain symptoms or if it's used to monitor treatment in men who have prostate cancer. "As a general screening for healthy men, I do not recommend it at all," he said.

Miller also doesn't recommend the prostate examination done by hand that physicians commonly give to middle-aged and older men, unless symptoms are present.

More information: For more about prostate cancer, try the U.S. National Library of Medicine.

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