PSA Test: New Studies, Same Old Questions

The conclusion? "After seven to 10 years of follow-up, the rate of death from prostate cancer was very low and did not differ significantly between the two study groups."

The authors acknowledged some limitations in their study, including the fact that treatment for prostate cancer may have improved so much as to negate any benefit that screening may have had. They also point out that it may yet be too early to draw a definite answer from the study, and that further follow-up of the men participating in this study may be warranted.

What about the European trial? That one is even more confusing.

In this trial, 182,000 men between the ages of 50 and 74 in seven European countries were randomly assigned to get a PSA test "at an average of once every four years" or to a control group that did not get screened. Of this group, 162,387 were actually part of the current report, and these men were between the ages of 55 and 69 years.

Half the men were followed for more than nine years, and half less than nine years. Eighty-two percent of the men who were offered screening got at least one PSA test. Of those who had at least one PSA test, 8.2 percent were diagnosed with prostate cancer, and of those who did not have the test, 4.8 percent had a diagnosis of prostate cancer made during the period of the study.

The end result was that the risk of death in the men who were screened was 20 percent less than those who were not screened. In more plain terms, according to the authors, "1,410 men would need to be screened and 48 additional cases of prostate cancer would need to be treated to prevent one death from prostate cancer."

When one considers all of the problems (urine incontinence, impotence, pain and bleeding among others) associated with treatment for prostate cancer, that is a lot of men left with a lot of symptoms to save one life.

When you dig deeper into the study, you begin to see some inconsistencies that may have influenced the results.

Recruitment and randomization procedures were not the same in every country that participated. Portugal stopped participating, and France joined late. All countries included men ages 55-69, but Sweden also included men who were 50-54. The Netherlands, Italy, Belgium and Spain included men up to the age of 74, and in Switzerland, men were screened up to the age of 75.

In all countries except Finland, men were randomly assigned on a "50-50" chance basis to screening or no screening. Finland decided to screen two men for every one in the control group.

Here is another interesting piece of information: In the European trial, 75.9 percent of the men who underwent prostate biopsy because of a PSA level of 3 or greater did not have prostate cancer.

The conclusion of this study?

"The ratio of benefits to risks that is achievable with more frequently screening or a lower PSA threshold than we used remains unknown," the authors wrote. "Further analyses are needed to determine the optimal screening interval in consideration of the PA value at the first screening and of previously negative results on biopsy."

Sounds like a draw to me.

There was an editorial that accompanied these two articles, which reported that, in the mode of "do as I do," 95 percent of male urologists and 78 percent of primary care physicians who are age 50 or over have had their own PSA tested. The author also noted that there has been a significant decline in deaths from prostate cancer since the early 1990s.

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