A man with no risk factors for prostate cancer can go his whole life without ever taking a PSA test, according to the American Urological Assn.
In a new clinical guideline unveiled Friday, the urologists said that only men between the ages of 55 and 69 should even consider getting a PSA screening test if they have no signs or symptoms of prostate cancer. Men should only get tested after discussing all the pros and cons with their doctors, and if they decide to get tested, they should not get tested again for at least two years, the guideline advises.
The PSA test measures prostate-specific antigen, an enzyme that helps liquefy semen. Here's a little background from a 2012 Los Angeles Times story:
When prostate cancers develop, PSA levels in the blood can start to climb. Other medical conditions, such as prostate inflammation and benign prostatic hyperplasia, can also cause PSA levels to rise.
The test has been routinely used as a screen for prostate cancer starting in middle age since the 1990s. The precise level of PSA in the blood or patterns of PSA change deemed suspicious vary somewhat from practice to practice.
About 16% of men will receive a prostate cancer diagnosis in their lifetimes, and 2.8% will die of it, according to the National Cancer Institute.
PSA testing has been falling out of favor in recent years. Many health experts say the test isn't very good at helping doctors figure out which men have prostate cancer that threatens their lives and which men have cancers that are so slow-growing that they're essentially harmless. However, the biopsies and treatments that follow a PSA test can cause significant health problems.
These are some of the reasons why the U.S. Preventive Services Task Force said last year that PSA testing should be abandoned as a screening tool. The task force is a government panel of experts who weigh the pros and cons of cancer screening tests and other preventive health measures.
At the time, the American Urological Assn. expressed "outrage" and called the task force's advice "inappropriate and irresponsible."
"There is strong evidence that PSA testing saves lives," Dr. Sushil S. Lacy, then president of the association, said in a statement.
Now the association is taking a more measured approach. The new recommendations are based on medical evidence from clinical trials instead of the "consensus opinion" of urologists, as was done in the past.
The guideline acknowledges that "prostate cancer screening itself is associated with a number of potential harms, both psychological and physical." For instance, the biopsy can cause pain, infection, blood in the urine or in semen and other side effects.
Some of those side effects are psychological, the guideline says: "There is considerable distress involved in the decision-making process, the biopsy and deciding among treatment options. Along with the stress due to PSA screening and unnecessary biopsies, the diagnosis of prostate cancer alone may incite severe psychological stress with one study showing an increased rate of suicide and cardiovascular events in newly diagnosed men."
The new guildeline also acknowledges that many men get treatment that's too aggressive for their disease. "Although prostate-cancer-specific mortality and the need for related palliative care is decreased by screening, quality of life may be impaired as a result due to lasting impairment in urinary, bowel and sexual function," the guideline states. "Thus, personal preferences should play a large role in both a decision to screen and in prostate cancer management if diagnosed."
With all this in mind, the association says that:
* Men under the age of 40 should not get a PSA test.
* Men between the ages of 40 and 54 should not consider PSA testing either unless they have a family history of prostate cancer or are in a group that is known to have an increased risk of the disease, such as African Americans.
* Men between the ages of 55 and 69 are most likely to benefit from PSA testing, but these men should weigh the benefits and harms of the test in consultation with their doctors. The association notes that 1,000 men must be screened over 10 years – and incur the risks involved with biopsies and treatment – in order to prevent a single death from prostate cancer.
* Men in this age group who do opt for screening should not be screened annually but should wait at least two years between tests.
* Men who are at least 70 years old or who have a life expectancy of less than 10 years should not get a PSA test.
Importantly, these guidelines do not apply to men with symptoms of prostate cancer.
"There is general agreement that early detection, including prostate-specific antigen screening, has played a part in decreasing mortality from prostate cancer," Dr. H. Ballentine Carter, chairman of the American Urological Assn. panel that developed the guideline, said in a statement. However, he added, "it's time to reflect on how we screen men for prostate cancer and take a more selective approach in order to maximize benefit and minimize harms."
You can read the full guideline online here.
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