Screening saves lives. It’s virtually a mantra when it comes to cancer.
But the prostate-specific antigen (PSA) test to screen for prostate cancer has come under fire recently as experts began to attribute it to a rise in the number of slow-growing, nonaggressive prostate cancers diagnosed and treated.
“We know that prostate cancer has been overtreated for generations,” says Jeffrey Montgomery, M.D., a urologist at the University of Michigan Health System.
A recent Northwestern University study, however, painted a different picture: finding skyrocketing rates of metastatic prostate cancer over a recent 10-year period, attributed in part to a 2012 U.S.
Preventive Services Task Force recommendation to discontinue PSA testing in all men.
Many critics, including the American Cancer Society, deemed the study’s methodology flawed.
And, last week, a research letter published online in JAMA Oncology cited stable numbers of advanced cases in men aged 50 and older during the same time frame (unlike the Northwestern findings, it used population incidence, rather than the number of cases, to account for demographic shifts).
Screenings, Montgomery says, have merit: A simple blood test can detect elevated levels of PSA — a substance released into the body by a man’s prostate gland — that could indicate the likelihood of cancer.
On the other hand, screenings might also prompt surgery, radiation and resulting side effects in low-risk patients who don’t need it.
Which is why results of the test, if a man receives one, should be analyzed carefully.
“We now observe more patients with prostate cancer than we treat,” Montgomery says.
He explained what men should know about PSA testing.
Are we seeing a rise in prostate cancer diagnoses?
Montgomery: Anecdotally between me and my partners, we’re tending to see more advanced cases of prostate cancer — and in younger men. I think that the decrease in PSA screening has affected this. Men are getting tested at a later age and less frequently.
We want to screen the younger men, men who are healthy, have a family history of longevity, or with a family history of prostate cancer that could really be impacted by the diagnosis of an intermediate- or high-risk prostate cancer.
There’s also a lot of work being done on new biomarkers that can better identify prostate cancer. Our goal is to screen the right person with the right test at the right time.
Do you agree with the universal guidelines to end PSA testing?
Montgomery: I think that these recommendations were made in haste and without really understanding how urologists were managing prostate cancer in real time.
What the task force was most concerned about was the overdiagnosis and overtreatment of low-risk prostate cancer. The vast majority of these patients are now observed.
They’re also very concerned about the impact on quality of life that prostatectomy or radiation therapy has — effects on urinary and erectile function — but the data they used for this recommendation was antiquated.
For instance, now upwards of 99 percent of our prostatectomy surgeries are done robotically, with improved outcomes for erectile function recovery and a significant improvement in urine control recovery.
Given the shift, how do you determine whether someone should be screened for prostate cancer?
Montgomery: I think the sweet spot for PSA screening is between age 50 and 70. Generally, I would say in men who are at higher risk — a first-degree relative: a son, a father or a brother with a history of prostate cancer — should get first evaluated with PSA at age 40 to 45.
African-American men are at a higher risk as well, as are Vietnam veterans exposed to Agent Orange.
For now, the PSA test is the most widely available tool we have for prostate cancer screening. It is not particularly specific for prostate cancer, but it is sensitive.
It identifies those men we should pay more attention to. It’s up to us as urologists once men are referred to us to determine whether a prostate biopsy is indicated.
Would you advise a patient to request a PSA if his physician discourages it?
Montgomery: We see situations in which a primary care doctor doesn’t offer a man PSA screening and the patient comes for a second opinion.
If a man wants to be screened for prostate cancer and he understands the risks and benefits of screening, he should be screened. It is up to us to take that PSA level in context.
It’s a matter of taking that PSA value and really understanding it beyond its face value. A single PSA value doesn’t necessarily dictate that a patient needs a prostate biopsy.
There’s a lot of consideration that goes into determining whether a patient requires further investigation.
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News source: Michigan Health. The content is edited for length and style purposes.
Figure legend: This Knowridge.com image is credited to Michigan Health.