Medicine
In the face of accumulating evidence and a U.S. Preventive Services Task Force finding that prostate-specific antigen (PSA) screening for prostate cancer does more harm than good, the most frequent response I hear from physicians who continue to defend the test is that PSA is all we have, and that until a better test is developed, it would be unethical to not offer men some way to detect prostate cancer at an asymptomatic stage. (However, these physicians for the most part don't question the ethics of not offering women screening for ovarian cancer, which a recent randomized trial concluded provides no mortality benefit but causes considerable harms from diagnosis and treatment.)
- Psa Redux: The Uspstf Finally Recommends Not Getting It!
. The US Preventive Services Task Force (USPSTF), the independent group of physicians and scientists who make recommendations to the government, medical community, and American people on the value of screening tests, recently came out with a new recommendation...
- Psa Screening By The Numbers: No Benefits, Many Harms
Previous studies found that two-thirds of men who receive prostate-specific antigen (PSA) screening for prostate cancer didn't have shared decision making with their physicians. If shared decision making occurred at all, patients were more likely...
- We Need To Know More About Psychological Harms Of Screening
Several years ago, a few colleagues and I performed a systematic evidence review to help update the U.S. Preventive Services Task Force's recommendations on screening for prostate cancer. One of our key questions asked about the harms associated with...
- Psa Screening For Prostate Cancer: A Bad Idea Then And Now
Few scientists have been fortunate enough to make a single discovery that ultimately revolutionized the practice of medicine. So one might expect Dr. Richard Ablin, who identified prostate-specific antigen (PSA) more than forty years ago, to take satisfaction...
- The Best Recent Posts You May Have Missed
Every other month or so, I post a list of my top 5 favorite posts since the preceding "best of" list on this blog, for those of you who have only recently started reading Common Sense Family Doctor or don't read it regularly. Here are some favorites...
Medicine
"Pure Custer": our obsession with the flawed PSA test
In the face of accumulating evidence and a U.S. Preventive Services Task Force finding that prostate-specific antigen (PSA) screening for prostate cancer does more harm than good, the most frequent response I hear from physicians who continue to defend the test is that PSA is all we have, and that until a better test is developed, it would be unethical to not offer men some way to detect prostate cancer at an asymptomatic stage. (However, these physicians for the most part don't question the ethics of not offering women screening for ovarian cancer, which a recent randomized trial concluded provides no mortality benefit but causes considerable harms from diagnosis and treatment.)
A few years ago, I read historian Stephen Ambrose's dual biography of Oglala Sioux leader Crazy House and Civil War cavalry general George Armstrong Custer, whose troops were routed by the Sioux at the famous Battle of Little Bighorn in 1876. One premise of the book is that the same aggressive instincts that served Custer so well during the Civil War - to always attack, even when the strength and disposition of his enemy was unknown - became fatal flaws when he became an "Indian fighter." For most of his post-Civil War career, Custer and his men wandered the Great Plains looking for someone to fight, and not particularly caring if the Indians he engaged in battle were actually at war with the U.S. Army. In one telling description of Custer's first major Western engagement, Ambrose writes:
Here was audacity indeed. ... Custer had no idea in the world how many Indians were below him, who they were, or where he was. His men and horses were exhausted. ... He was going to attack at dawn from four directions at once. He had made no reconnaissance, held nothing back in reserve, was miles away from his wagon train, and had ordered the most complex maneuver in military affairs, a four-pronged simultaneous attack. It was foolish at best, crazy at worst, but it was also magnificent and it was pure Custer.
If readers of American Indian descent will kindly forgive my making this analogy with their 19th century ancestors, this passage is strikingly similar to the way we diagnose and manage prostate cancer. The vast majority of American Indians by this time had either signed peace treaties or were content to leave settlers alone. Under pressure to "do something" about a few troublesome tribes, however, the U.S. Army sent the overaggressive Custer out to do battle with whatever "warriors" he could find, assuming that in the process he would either kill, capture, or scare off those who aimed to do them harm.
That's pretty much what we do by deploying the PSA test to screen for prostate cancer. We cast as wide a net as possible, doing harm at every step of the way: false positives, adverse effects of prostate biopsies, and overdiagnosis and overtreatment of abnormal-appearing cells that we identify - usually inaccurately - as potentially lethal. For every man whose life may be extended by treatment, 30 to 50 will be treated for no benefit, and 10 to 20 will sustain permanent physical harm. And our continuing obsession with this flawed screening test not only flies in the face of evidence, it's pure Custer.
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This post first appeared on Common Sense Family Doctor on November 18, 2011.
**
This post first appeared on Common Sense Family Doctor on November 18, 2011.
- Psa Redux: The Uspstf Finally Recommends Not Getting It!
. The US Preventive Services Task Force (USPSTF), the independent group of physicians and scientists who make recommendations to the government, medical community, and American people on the value of screening tests, recently came out with a new recommendation...
- Psa Screening By The Numbers: No Benefits, Many Harms
Previous studies found that two-thirds of men who receive prostate-specific antigen (PSA) screening for prostate cancer didn't have shared decision making with their physicians. If shared decision making occurred at all, patients were more likely...
- We Need To Know More About Psychological Harms Of Screening
Several years ago, a few colleagues and I performed a systematic evidence review to help update the U.S. Preventive Services Task Force's recommendations on screening for prostate cancer. One of our key questions asked about the harms associated with...
- Psa Screening For Prostate Cancer: A Bad Idea Then And Now
Few scientists have been fortunate enough to make a single discovery that ultimately revolutionized the practice of medicine. So one might expect Dr. Richard Ablin, who identified prostate-specific antigen (PSA) more than forty years ago, to take satisfaction...
- The Best Recent Posts You May Have Missed
Every other month or so, I post a list of my top 5 favorite posts since the preceding "best of" list on this blog, for those of you who have only recently started reading Common Sense Family Doctor or don't read it regularly. Here are some favorites...