The United States Preventative Services Task Force (USPSTF) is a government commission that is responsible for reviewing the medical literature (i.e. research studies) and then formulating screening guidelines for various diseases. The USPSTF recently concluded that screening for prostate cancer with a digital rectal exam (DRE) or a PSA blood test does more harm than good and this is why. Both DRE and PSA testing can and do increase the number of prostate cancers that are detected—the problem is that there appears to be no mortality benefit (no lives saved on average) for doing this. How can this be??? Let’s first look at the numbers and then we’ll talk about the explanation. Before DRE/PSA screening an American man had a 1:11 chance of being diagnosed with prostate cancer and after DRE/PSA screening the number is 1:6. In other words, DRE/PSA screening has nearly doubled the cases of prostate cancer that are detected by physicians. The problem is that the chance of an American man dying from prostate cancer hasn’t changed—it was 1:34 before the DRE/PSA screening era and that number hasn’t changed! In other words, we’re detecting a whole lot more prostate cancer but it isn’t doing any good, at least not on average when you look at the U.S. population.
Is this to say that prostate cancer screening never does any good? Absolutely not. If you happen to be one of the rare men who has a potentially lethal prostate cancer and it is caught early and removed, then DRE/PSA screening just saved your life. The problem is, and it is a rather large problem, that MOST men eventually get prostate cancer and most men never suffer any problems from it—they end up dying from something else that is unrelated before their prostate cancer causes any problems. This is because prostate cancer is usually an incredibly slow growing cancer—sometimes it isn’t, but most of the time it is and you can (and many of the male readers probably are!) live with it for decades and never have any symptoms. Again, that’s not to say that prostate cancer can’t be deadly and rapidly progressive, because it most certainly can be—the only cancer that kills more American men than prostate cancer is lung cancer. But this is relatively rare compared to the cases of indolent (slow-growing) prostate cancers.
In a nutshell, routine DRE/PSA screening appears to have resulted in physicians detecting a lot more clinically irrelevant, indolent prostate cancers without decreasing the rate of death from malignant, deadly prostate cancer. This is a major problem because popping positive on a routine DRE/PSA screen sets you up for a biopsy, probably followed by either surgery, radiation therapy, hormonal therapy, or a combination of the above. All of these treatments have substantial side-effects including a 1:200 chance of death on the operating table during surgery, urinary incontinence (you pee on yourself for the rest of your life), erectile dysfunction, and bowel dysfunction. Again, DRE/PSA screening followed by biopsy and treatment does save some lives—but it results in a heck of a lot more men having nasty side-effects from the treatment of a cancer that never would have bothered them in the first place because it was so slow growing that something else would have killed them first (a heart attack, stroke, car accident, etc.).
While the USPSTF recommends against prostate cancer screening, they have caught a lot of flak from the urological and cancer societies for this position. Urologists (doctors who specialize in the genitourinary tract, including the prostate) especially are up-in-arms over the new USPSTF recommendations, but the problem is that both urological and cancer societies have a vested interest in this issue (they make money through cancer screening and the increased biopsy and treatment procedures that result from it). On the other hand, the USPSTF is a neutral body—guess whose opinion I give more weight (it’s the USPSTF, in case you didn’t recognize my sarcasm). The USPSTF isn’t saying that DRE/PSA screening isn’t indicated for some men—if you have a history of multiple family members that have died from prostate cancer then you should definitely speak with your physician about the risks-vs.-benefits of screening. What they are saying is that routine DRE/PSA screening of every man does more harm than good on average and that this position is well-supported by a large body of high quality medical research.
Hoffman, RM. Screening for prostate cancer. In:UpToDate. http://www.uptodate.com/contents/screening-for-prostate-cancer?source=search_result&search=prostate+cancer+screening&selectedTitle=1%7E17. Accessed March 27, 2013.
Dr. Leonardo Noto
Physician and Author of Medical School 101, Intrusive Memory, The Life of a Colonial Fugitive, and The Cannabinoid Hypothesis.
Author Bio: Dr. Leonardo Noto is the nom de plume of a former airborne battalion surgeon who is now in civilian practice. Dr. Noto is the author of four books and he also writes for a medical education corporation that assists medical students, interns, and residents as they prepare for the medical board examinations. Dr. Noto is the proud father of an extremely spoiled 12-month-old American Bulldog who enjoys slobbering everywhere and tearing up things that he is not supposed to! Dr. Noto is an amateur practitioner of muay Thai and Brazilian jiu jitsu and he recently began learning to play the guitar (but he is currently a quite terrible musician, as his neighbors will readily attest).
Remember to discuss all health concerns with your personal physician (I don’t count!) before making any medical decisions. www.leonardonoto.comis intended to present general medical information for entertainment purposes and not as specific guide to any medical treatment. The author has made every effort to present accurate information; however, due to the ever-changing nature of medicine and the intrinsic caveats that are inherent in any particular case, no medical decisions should ever be made based on information gleaned from the internet (duh!). The internet and self-education are great, but they don’t replace your Doc!