The U.S. Preventive Services Task Force has issued a new draft recommendation on prostate-cancer screening that effectively rolls back its controversial 2012 assessment that the “expected harms” of the PSA test outweigh its “small potential benefit,” and, therefore, the test should not be routinely done.
Now the USPSTF is recommending that clinicians inform men ages 55 to 69 of the risks and benefits of the prostate-specific antigen (PSA) test and help them to make individualized decisions about being tested. The task force continues to recommend against routinely testing men 70 and over, however, because prostate cancer is slow-growing, and both the 10-year survival rate and the overdiagnosis rate for prostate cancer in this age group are high.
I gave a lot of ink in my book, “Our Parents in Crisis,” to the prostate gland, benign prostatic hyperplasia (BPH, aka an “enlarged” prostate), and prostate cancer. Since its FDA approval in 1994, urologists have used the PSA blood test to screen for evidence of prostate cancer. A significant problem with the test is that it is not cancer-specific.
PSA is an enzyme produced by the prostate and secreted during ejaculation into ducts that empty into the urethra. Usually, only tiny amounts of PSA are present in the blood, but abnormalities of the prostate can create an opening for more to pass.
PSA is measured by nanograms (ng) per milliliter of blood, a nanogram being a billionth of a gram. High blood levels of PSA may indicate problems, such as cancer, BPH, infections, and other conditions—or they may not. Many false positives occur, as do false negatives. A PSA blood level below 4.0 ng/mL is usually no cause for concern, but a man with prostate cancer may test low.
Overdiagnosis of prostate cancer results in overtreatment. Prostate biopsies pose the risk of infection, blood clots, and other harms, and surgery, intensive radiation, and other interventions can cause temporary or permanent urinary incontinence, erectile dysfunction, bowel damage, and other debilitating consequences.
The USPSTF’s full draft recommendation is available for public comment on its website until May 8, 2017, at https://screeningforprostatecancer.org/.
I reprint below an edited excerpt from my book about the PSA-test controversy, in which I conclude, as the USPSTF does now, that men between ages 50 and 70 should make individualized decisions about testing in consultation with doctors whom they trust and who know them well:
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In May 2012, after reviewing available scientific evidence, the U.S. Preventive Services Task Force concluded that the “expected harms” of the prostate-specific antigen (PSA) test “are greater than [its] small potential benefit.” (1)
The task force gave this blood test, as a routine screening practice for prostate cancer, the lowest grade it assigns: a “D,” meaning no recommendation. A “C” grade would have been a recommendation that “depends on the patient’s situation.” (2)
The USPSTF is an independent panel of primary-care physicians and epidemiologists who are appointed, funded, and supported by the U.S. Dept. of Health and Human Services’ Agency for Healthcare Research and Quality. . . .
According to the panel, the PSA test helps to save the life of just one man in 1,000 and steers many more who would never die of prostate cancer toward unnecessary surgery and treatment.
“For every man whose life is saved by PSA testing,” the task force said in a statement, “another one will develop a dangerous blood clot, two will have heart attacks, and 40 will become impotent or incontinent because of unnecessary treatment.” (3)
The USPSTF’s “D” grade principally affects healthy men between ages 50 and 70. According to Johns Hopkins urologist H. Ballentine Carter, for men age 70 and older, “the likelihood that routine PSA testing will be [at all] beneficial is extremely low.” (4)
Many men over age 50 get a digital rectal exam [DRE] and blood drawn for a PSA test during a regular checkup with their primary-care physician. Research suggests that PCPs too often routinely order PSA screening without assessing the patient’s family history, race, age, life expectancy, overall health, and other patient-specific factors. (The incidence of prostate cancer among African-American men is greater than among men of other races.)
If the test suggests a problem—and false-positive results are common—they then “wash their hands of responsibility once the patient is referred to a specialist for prostate-cancer treatment,” according to two Harvard primary-care doctors in a 2011 New England Journal of Medicine article. (5)
Once a patient is in the care of a urologist, his potential for overtreatment and, thus, exposure to harm, increases. Surgery, intensive radiation, and other interventions can cause temporary or permanent urinary incontinence, erectile dysfunction, bowel damage, and other debilitating consequences.
That men in the United States have a 17 percent chance of being diagnosed with prostate cancer during their lifetimes, but only a 3 percent chance of dying from it, suggests that conservative medical management may be appropriate for many. (6) And yet, most men diagnosed with low-risk prostate cancer choose to undergo active treatment such as surgery or radiation, regardless of their age and life expectancy and despite the risks. Anxiety and fear—and urging from their urologists—prevent them from opting for watchful waiting only. (7)
According to Richard J. Ablin, Ph.D., the pathologist involved in the 1970 discovery of PSA, and Allan S. Brett, M.D., a University of South Carolina medical professor, PSA test “thresholds” for physician action fall in the range of 2.5 to 4.0 ng per millileter. (8)
“Action” by physicians has tended to mean PSA retesting, sometimes several times a year; prostatic biopsies, sometimes repeated; and even the use of antibiotics to lower mildly elevated PSA blood levels in asymptomatic men with presumed prostatitis (inflammation of the prostate). (9) Depending on the doctor, “watchful waiting” can mean active surveillance, with regular testing, or simple observation, without testing. [A biopsy poses the risks of] infection, bleeding, pain, urinary problems, and other “complications.”
Once a cancer diagnosis is made, a urologist “stages” the tumor(s) for purposes of prognosis. Besides DRE and PSA test results, he or she typically relies on a grading of the cancer’s aggressiveness, which a pathologist calculates from the tumor patterns he or she detects in biopsied tissue. Because Minnesota Veterans Administration hospital pathologist Donald Gleason devised this cancer-grading scale in the 1960s, the calculation is known as a Gleason score.
“Low-risk” or “low-grade” prostate cancers are those in which no nodule, or only a small nodule, is felt during a DRE; the patient’s Gleason score is 6 or lower; and his PSA blood level is below 10 ng/mL. (10)
If tissue and biochemical analysis suggests that the cancer has spread, physicians usually proceed with imaging tests, including CT, PET, and bone scans, to find out the extent and location of the cancer. Many doctors, however, will order a full battery of such imaging tests even in the absence of metastasis.
The American Society of Clinical Oncology strongly recommends that imaging not be used to stage low-risk cancers because of the costs to the patient and the healthcare system. Scans sometimes reveal abnormal-looking areas that prove, after expensive additional procedures and tests are performed, to be noncancerous. Meanwhile, patients endure needless worry and hours of wasted time. Imaging tests also expose patients to radiation and, thus, increase their risk of cancer. (11)
Cheers and Jeers
When the USPSTF withdrew its support of the PSA test, physicians responded with both cheers and jeers.
The 19,000-member American Urological Association was reportedly “outraged” by the action. The Large Urology Group Practice Assn., which represents 1800 urologists nationwide—purportedly 20 percent of all practicing urologists—said it was “appalled” by the panel’s “irresponsible and inexplicable” recommendation. But the decision pleased other physicians, including oncologists, who believe prostate cancer is both overdiagnosed and overtreated.
PSA testing has become “big, big money” for testing companies, physicians, and hospitals, said the chief medical officer of the American Cancer Society, who praised the task force for “taking a really hard line here.” (12) According to PSA discoverer Richard Albin, the nation’s annual bill for PSA screening is at least $3 billion, much of it paid by Medicare and the U.S. Veterans Administration. He has called the test’s popularity “a hugely expensive public health disaster.” (13)
Dr. Carter agrees that “An elevated PSA score can lead to a prostate biopsy that turns out to be unnecessary. Conditions other than cancer can cause PSA levels to rise, and about one in four men who have a positive PSA test turns out not to have prostate cancer. Further, when biopsies do reveal signs of prostate cancer, 30 to 50 percent of these cancers (depending on a man’s age) won’t be harmful—even if left untreated.”
Nonetheless, Carter is reluctant to throw out the baby with the bath water, saying, “PSA screening is currently the best test available for early detection of prostate cancer.” (14)
Geriatrician-epidemiologist Dr. Paulo H.M. Chaves, M.D., Ph.D., of the Johns Hopkins Center on Aging and Health, disagrees. He supports the USPSTF’s recommendation. Chaves stresses that the PSA test is too often inaccurate; that all men of a “certain age” have cancerous cells in their prostates; and that prostate cancer progresses so slowly that men who have it typically die from another cause. (15)
My own view is that men should make informed individualized decisions about this screening test in consultation with physicians whom they trust to know them and to serve their best interests. They should ask their doctors about the benefits and costs of PSA testing. What does the clinical evidence show? As always, I recommend doing your own homework. You can start with my endnotes. (16)
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1. Among the clinical studies the task force evaluated was a nationwide trial known as PIVOT, which stands for Prostate Cancer Intervention Versus Observation Trial.
From November 1994 through January 2002, PIVOT researchers followed 732 men who were diagnosed with localized prostate cancer (no metastasis) and randomly assigned to a radical prostatectomy or to observation. Each trial subject had to have a PSA value of less than 50 ng/mL and be 75 years old or younger, with a life expectancy of at least 10 years. The average age of the group was 67; the average PSA value was 7.8 ng/mL.
Among their findings, the researchers concluded that men with low-risk prostate tumors in the observation group were no more likely to die of prostate cancer than men with a similar risk in the prostatectomy group. Significantly, only 52 of the 354 deaths that did occur among the low-risk group were attributable to prostate cancer or its treatment. Among men with a PSA value greater than 10 ng/mL, however, radical prostatectomy was associated with reduced mortality from all causes.
Timothy J. Wilt, Michael K. Brawer, et al, “Radical Prostatectomy Versus Observation for Localized Prostate Cancer,” New England Journal of Medicine 367 (2012): 203-13. See also H. Ballentine Carter, Johns Hopkins Medicine, “Prostate Cancer: To Treat or Not to Treat?,” Health After 50, vol. 24, issue 12, January 2013, pp. 1-2.
2. USPSTF at http://www.uspreventiveservicestaskforce.org/prostatecancerscreening.htm.
3. Brian Vastag, “Panel: Prostate Test Shouldn’t Be Routine,” The Washington Post, May 22, 2012, p. A3. See generally USPSTF at http://www.uspreventiveservicestaskforce.org/prostatecancerscreening.htm.
4. H. Ballentine Carter, M.D., Johns Hopkins Medicine, “Should You Be Tested for Prostate Cancer?,” Health After 50, vol. 23, issue 11, January 2012, p. 5. Carter advises men who choose to be screened to have their first PSA test at age 40. For men who get a PSA test at age 50, he recommends a follow-up testing schedule dependent on the results. His cut-off action threshold is 3 ng/mL or above. With a test of this level, he recommends that the patient “consult a urologist.” Ibid.
See also Manoj Jain, “Are We Relying Too Much on Cancer Screening? False Positives Show Need to Adjust Patients’ Expectations of Tests,” The Washington Post , Nov. 1, 2011, p. E5. Jain, an infectious-disease specialist and adjunct assistant professor at the Rollins School of Public Health at Emory University in Atlanta, concludes that when he turns 50, he will skip the PSA test.
5. Mary F. McNaughton-Collins and Michael J. Barry, “One Man at a Time—Resolving the PSA Controversy,” New England Journal of Medicine 365 (2011): 1953.
6. Wilt, Brawer, et al, “Radical Prostatectomy Versus Observation for Localized Prostate Cancer,” p. 204.
7. Carter, “Prostate Cancer: To Treat or Not to Treat?,” p. 1.
8. Allan S. Brett and Richard J. Ablin, “Prostate-Cancer Screening—What the U.S. Preventive Services Task Force Left Out,” New England Journal of Medicine 365 (2011): 1950.
9. Carter, “Should You Be Tested for Prostate Cancer?,” pp. 4-5; and Carter, “Prostate Cancer: To Treat or Not to Treat?,” p. 2.
10. Carter, “Prostate Cancer: To Treat or Not to Treat?,” p. 2; and American Society of Clinical Oncology, “Hard Decisions About Cancer: 5 Tests and Treatments to Question,” Choosing Wisely, at http://www.choosingwisely.org.
11. American Society of Clinical Oncology, “Hard Decisions About Cancer: 5 Tests and Treatments to Question,” Choosing Wisely, at http://www.choosingwisely.org.
12. Vastag, “Panel: Prostate Test Shouldn’t Be Routine,” endnote 3, supra; American Urological Association, “AUA Speaks Out Against USPSTF Recommendations,” available on the AUA website, http://www.auanet.org/content/homepage/homepage.cfm; and Large Urology Group Practice Association at http://lugpa.org/defaault.aspx. See also McNaughton-Collins and Barry, “One Man at a Time—Resolving the PSA Controversy,” endnote 5, supra, pp. 1951-53.
13. Richard J. Ablin, “The Great Prostate Mistake,” The New York Times, March 9, 2010, at http://www.nytimes.com/2010/03/10/opinion/10Ablin.html.
14. Carter, “Should You Be Tested for Prostate Cancer?,” p. 5.
15. Paulo H.M. Chaves, M.D., Ph.D., “Addressing the Well-Being of Older Adults: Millions and More at a Time,” lecture in “Aging and Health,” Johns Hopkins University Mini-Medical School, Oct. 20, 2011.
16. See James A. Colbert and Jonathan N. Adler, “Prostate Cancer Screening—Polling Results,” New England Journal of Medicine 367 (2012): e25.