The Benefits of Prostate Exams

Chicago Tribune

There is now a partial answer to one of the most controversial questions in medicine: whether men should get blood tests that screen for prostate cancer.

Experts say a new study shows that for men likely to die within 10 years - whether due to age or illness - the answer is no.

The study of nearly 77,000 men, the most extensive investigation of its kind in the U.S., found that although blood tests for prostate-specific antigen (PSA) identify more cancers, they do not end up saving more men's lives in the first 10 years of follow-up.

That might seem counterintuitive, but many prostate tumors grow slowly and are not dangerous, so early detection is not as critical as it is for other cancers. Meanwhile, there are significant downsides to treatment, mainly incontinence and impotence.

The study, sponsored by the National Cancer Institute, was designed to help answer a fundamental question: whether the potential benefits of PSA screening - identifying disease early, saving lives - are outweighed by the potential risks, including the effects of treatment and the anxiety of a cancer diagnosis.

For men in their 50s and 60s who aren't considered at high risk, the answer is still not clear, because the men haven't been followed long enough yet to offer decisive guidance. The study will continue for several years until that data is collected.

But because the findings regarding older and seriously ill men were viewed as important, they were released now and published online in the New England Journal of Medicine.

They demonstrate that there's little reason for men with life expectancies of less than 10 years to undergo PSA testing because they are unlikely to benefit, said Dr. Gerald Andriole, lead author of the study and chief urologic surgeon at Washington University School of Medicine and Barnes-Jewish Hospital in St. Louis.

The don't-test group includes men older than 75 whose expected life span is less than a decade, and those with life-limiting conditions such as serious heart disease or poorly controlled diabetes.

Experts say African-American men and men with a family history of prostate cancer are classified as high risk and should get prostate cancer tests beginning in their 40s. For other men, those in their 50s, 60s and early 70s, "I'm not confident we can say at this point what to do with them," Andriole admitted.

One criticism of the U.S. study is that it compares men who were prescribed six PSA tests to men who weren't told to be tested but also weren't forbidden to do so, a less-than-optimal research design.

Most physicians contacted by the Chicago Tribune said they would continue to recommend annual PSA testing to men 50 and older, but would use the results from the study to inform discussions with patients of the potential risks and benefits of the test and prostate cancer treatment.

"The way I think about it, the test gives valuable information to me and my patients," said Dr. Scott Eggener, assistant professor of urology at the University of Chicago Medical Center. "The key fork in the road isn't really having the test or not: It's deciding whether to be treated or not."

Digital rectal exams also are used to detect prostate cancer, but the exams detect tumors an average of 10 years later than PSA testing. In the U.S., they're recommended to low-risk men starting at age 50.

The new research will undoubtedly reinforce concerns over the large numbers of men who are getting PSA tests, then being diagnosed with cancer and agreeing to treatment with its attendant side effects, even though their tumors are slow-growing and almost surely not dangerous.

Up to 40 percent of tumors identified through prostate cancer tests fall in this category, according to a separate study published last week in the Journal of the National Cancer Institute.

"There is no question that there are men who are getting the side effects (of prostate cancer treatment) without getting the benefits," said Dr. Edward Gelmann, chief of the division of hematology and oncology at Columbia University Medical Center in New York.

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