The value of two regular common screening tests-for prostate and cervical cancers-were called into question earlier this month by yet more professional medical associations. Today we’ll report on prostate cancer screening with the PSA test. Tomorrow: Pap tests for cervical cancer.
A statement issued by the clinical guidelines committee of American College of Physicians (ACP) said, “The potential harms of PSA testing outweigh the benefits for most men, such that testing should occur only after a careful discussion between physician and patient …”
Readers of this blog are familiar with the evolving awareness of potential harms from the prostate specific antigen (PSA) test. Although one life is saved for every 1,000 people screened over a 10-year period, more than 100 of those same 1,000 men will produce suspicious results when there is either no cancer or a cancer that is growing so slowly (or not at all) as to produce no threat.
For most men, a positive test means having a biopsy, whose risks include pain, fever, bleeding, infection and hospitalization. If cancer is detected, 9 in 10 men will have surgery and/or radiation even when the tumors are not life-threatening. Their side effects include impotence, urinary incontinence and blood clots.
“ACP recommends that clinicians should not screen for prostate cancer using the prostate-specific antigen test in patients who do not express a clear preference for screening,” the panel said.
As explained on MedPageToday.com, the guideline statement is a melding of recent recommendations issued by other groups, including the American College of Preventive Medicine (ACPM), American Cancer Society (ACS), American Urological Association (AUA) and the U.S. Preventive Services Task Force (USPSTF).
The USPSTF doesn’t recommend routine PSA screening, but for men who choose to have the test, it advises that they being fully informed of the benefits and harms.
“Studies have shown,” said the ACP statement, “that up to one-third of men screened for prostate cancer were unaware that they were being tested, and many men who were aware that they were tested do not receive an adequate discussion of the benefits and harms of screening.”
The ACP panel says doctors should address these issues with every patient:
- PSA testing is controversial.
- PSA tests can detect prostate cancer, but for most men, the harms outweigh the benefits.
- Relatively few prostate cancers prove to be aggressive and cause death; most are likely to be slow-growing and nonfatal.
- Most men who are not screened do not develop prostate cancer and die of other causes.
- Men who choose to be tested are much more likely to have prostate cancer diagnoses compared with men who decline to be screened.
- PSA tests do not distinguish between serious and nonserious cancers.
- At most, PSA testing prevents one prostate cancer death per 1,000 men screened after 11 years of follow-up.
- Screening can lead to many potential harms, some of them serious (including unnecessary biopsies and surgery).
- PSA testing can “open the door to more testing and treatment that a man may not actually want and that may actually harm him.”
- Ongoing studies will provide more information about PSA testing, and recommendations might change.
This patient-doctor discussion applies to men ages 50 through 69, said the ACP. Men outside that range who are at average risk or developing prostate cancer, or who have a life expectancy fewer than 10 to 15 years, derive very little benefit from PSA testing.
Men at high risk-those with a family history of prostate cancer, smokers, the obese, African Americans, those older than 65-also should engage in the shared decision, said the ACP. The panel said there’s a lack of evidence that screening high-risk patients changes outcomes appreciably as compared with screening average-risk men.
Guidelines for how often women should get pap tests, which are used to detect cervical cancer, were updated this month as well. More on that in our next blog.