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As a retired primary care physician, I felt the need to respond to the May 20 commentary "Prostate cancer: Questions of medicine, money and risk." The author is unfortunately dealing with regionally advanced prostate cancer and advocates for more extensive screening to detect early prostate cancer. He finds it astonishing that some screening guidelines say not to screen for prostate cancer at all. On the face of it, that does seem ridiculous. But it isn't so cut and dried.

Decades ago, the only screening for prostate cancer was a rectal exam. Famous for how much patients disliked it (doctors weren't enthralled, either), and how poor it was at detecting prostate cancer early. Essentially useless. Then came the discovery of prostate-specific antigen (PSA) blood test as a tool to monitor people who were receiving treatment for prostate cancer. It was very useful for that purpose. It was suggested that this test could be used for early detection of prostate cancer, although there was a wide variation in individuals' levels who did not have cancer, some people with aggressive cancer had low levels, and people with levels two or three times normal had no cancer. So it wasn't a great test for screening because of those false negatives and false positives, but it was what we had.

And that screening did find cancers that we wouldn't have found otherwise. The problem was, we couldn't tell if they were "bad" cancers, the kind you might die of, or the "not so bad" cancers that might never had caused symptoms. We imaged the prostate, did biopsies and then had the pathologist try to predict the cancer's behavior by assigning it a score based on microscopic appearance.

Initially, almost everyone was offered either surgery or radiation as a treatment to eliminate the cancer, unless their life expectancy was 10 years or less. Treatment back then almost always resulted in permanent loss of sexual function and, oftentimes, incontinence. But we saved lives, right? Well, the numbers weren't great.

Historically, men have had about a 2% chance of dying from prostate cancer and a 6% chance of being diagnosed with it in their lifetime. After years of doing PSA screening, studies determined that those men screened had about a 12% chance of being diagnosed and a 1.8% chance of dying from it. Ten-year survival after diagnosis was about 90%, no matter what you did. So your chances of being diagnosed was doubled, but only 2 men out of 1,000 had their lives saved. Many men were needlessly frightened, and many lost sexual and urinary function. So that is where the U.S. Preventive Services Task Force (USPSTF) came up with its recommendations.

A couple more things:

Medicine does move forward, and prostate cancer screening is more nuanced these days. Better tests are always being investigated, and doctors and patients will often delay treatment ("active surveillance") until the cancer's behavior is recognized as advancing. Surgery has also improved, with ongoing research of promising new treatments. Some patients do have a higher risk of dangerous prostate cancer, and they should be screened. But we don't have all the numbers yet, regarding the success of these newer programs. And, therefore, prostate screening is still controversial. Talk to your doctor.

Finally, the commentary's author implies that the decision not to screen might be a money decision. This is not the case. It is based on risks and benefits, length of life and quality of life. I don't know any doctor who brings money into it. Most insurance plans are mandated to cover screening. Perhaps an uninsured patient would opt out, but that is a whole other topic.

David Brockway, of Hopkins, is a retired physician.