The Pros and Cons of Testing PSA Levels for Prostate Cancer – GWC Mag

Below is an approximation of this video’s audio content. To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video.

While 64 percent of men develop hidden prostate cancers by their 60s, the lifetime risk of being diagnosed with prostate cancer is only about 11 percent (and the risk of dying from prostate cancer is 2.5 percent at the average age of 80). So, most men develop prostate cancer, but they die with their tumors rather than from their tumors. Most men with prostate cancer live their whole lives never knowing they even had it. That’s one of the problems with screening for it. Many prostate cancers that are detected may never have led to harm even if they’d gone undiscovered. Nonetheless, not all men are so lucky. About thirty thousand Americans die each year from prostate cancer. So, should you get a PSA prostate screening test or not?

PSA stands for prostate specific antigen, an enzyme secreted by cells of the prostate to liquify semen and cervical mucus to facilitate fertilization. Elevated levels in the blood can be a sign of prostate cancer, which led to FDA approval as a screening test for the early detection of prostate cancer in the 1990s. If it comes back high, the test is usually repeated. If it’s still high, the next step is typically an ultrasound-guided biopsy of the prostate through the rectum. If there’s cancer, then options include surgery, radiation, and chemotherapy, or a delayal of treatment.

However, the USPSTF, the U.S. Preventive Services Task Force, the main independent scientific panel that sets evidence-based clinical prevention guidelines, recommended against routine PSA screening, as does the American College of Preventive Medicine, the American Academy of Family Physicians, and the vast majority—85 percent—of professional medical societies in developed countries around the world opposed.

In 2018, though, the USPSTF shifted from a summary judgement against to “the decision to be screened for prostate cancer should be an individual one,” which is more in line with the “shared decision-making” stance of the American Urological Association, the American College of Physicians, and the American Cancer Society. In other words, men should be informed about the risks and benefits, and decide for themselves. However, men who are on the fence and don’t express a clear preference in favor of screening should not be screened, according to the latest USPSTF recommendations.

More recently, an international panel of experts concluded that clinicians need not feel obligated to systematically bring it up, judging that most men would decide to decline PSA testing, given the clear harms and small and uncertain benefits. That, however, is up to you. I personally declined, but let’s run the numbers.

Similar to the 92 percent of women who didn’t know or overestimated the mortality reduction from mammograms by tenfold or more, 89 percent of men vastly overestimated the benefits of prostate cancer screening, or simply had no idea. Most thought 50 prostate cancer deaths could be prevented out of 1,000 men regularly screened, when in reality, it’s more like one. But doesn’t even a one in 1,000 chance of not dying from cancer make a few blood tests worth it? The downsides are more than inconvenience, though.

About one in seven men who undergo PSA screening will test positive, yet in two-thirds of the cases, the biopsy results will be normal. So, out of the 1,000 men regularly screened, about 150 will have a false alarm and be biopsied unnecessarily, which can cause minor complications like pain and bloody ejaculate, or in approximately 1 percent of cases, more serious complications like blood-borne infections that require hospitalization. The greatest harm, though, is overdiagnosis. Unnecessary biopsies are bad enough, but nothing compared to unnecessary cancer treatment.

Large-scale randomized trials suggest that 20 to 50 percent of men diagnosed with prostate cancer would have never become symptomatic in their lifetime. They never would have been any wiser had they not been screened, but now they may be needlessly heading to the operating table. About three in 1,000 men die during or soon after radical prostatectomy. That may help explain why there appears to be no overall mortality benefit to prostate cancer screening. For every life that is saved, another may be extinguished for a cancer they never would have even known about.

Another 50 in 1,000 men end up with serious surgical complications. Even if the surgery goes smoothly, about one in five men develop long-term urinary incontinence requiring the use of pads, and most men—two out of three—will experience long-term erectile dysfunction. Most men who receive radiation therapy also experience long-term sexual erectile dysfunction, and up to one in six experience long-term bowel issues, such as fecal incontinence. If this was saving your life, it would be worth it; but over 16 years, rather than being saved from a prostate cancer death by screening, it may be 25 times more likely that you were instead overdiagnosed with a cancer that wouldn’t have bothered you. Yet, you come away after treatment thinking the PSA test saved your life. It’s like with the mammograms. The people who have been harmed the most—unnecessary cancer treatment—feel as though they’ve been helped the most.

Please consider volunteering to help out on the site.