Overtreatment of early prostate cancer
Posted by medconsumers on August 6, 2010
In the 20 years since the screening PSA blood test for prostate cancer was introduced, it has become increasingly obvious that widespread use is causing far more harm than good—namely, the unnecessary treatment of cancers destined to remain dormant and never produce symptoms. The latest evidence comes from researchers who looked at treatment patterns of U.S. men whose cancers were detected at the earliest stage. The results raise questions not only about their overly aggressive treatment but also the PSA test level for sending them off for the biopsy which starts the whole process.
Keep in mind that doctors still cannot tell the difference between the prostate cancers that are going nowhere and the small minority that will turn aggressive and deadly. The new study found that over 75% of the men whose prostate cancers were least likely to spread or become lethal underwent a radical prostatectomy or radiation therapy. The severe adverse effects of each include impotence and incontinence.
The study, led by Yu-Hsuan Shao, PhD, Cancer Institute of New Jersey, appeared in the Archives of Internal Medicine. It drew on data from U.S. cancer registries, specifically about the treatment of 123,934 men with newly diagnosed prostate cancer from 2004 to 2006.
The advanced age of the men in this study is a cause for major concern. Almost 69% of men age 65 to 74 and about 40% of those over 75 had their prostates surgically removed or irradiated. This was described as “troubling” in the accompanying editorial because men 65 and older cannot expect any prostate treatment to prolong life. The editorialists, Richard M. Hoffman, MD, and Steven B. Zeliadt, PhD, cite a landmark 2005 Scandinavian trial that randomly assigned men with prostate cancer to receive immediate prostatectomy or “active surveillance” (aka watchful waiting). The surgery increased survival only for men, age 65 and younger. (To see how modest the survival benefit is even for younger men, click here for results from two 2009 studies.)
Also at issue is the PSA level at which a biopsy is recommended. The men treated aggressively in this study had “a PSA threshold below 4.0 ng/mL.” At a time when some researchers are arguing for lowering this threshold even further, Shao and colleagues made it clear that—given their findings—this would only make a bad situation worse. “Lowering the biopsy threshold but retaining our inability to distinguish indolent from aggressive cancer might increase the risk of overdiagnosis and overtreatment.”
The study was funded by the National Cancer Institute, the Cancer Institute of New Jersey, and the Robert Wood Johnson Foundation.
For more information
Go to the prostate cancer section of the National Cancer Institute’s database to read about screening, treatment options, and active surveillance, which describes the most conservative option of no treatment. This is a remarkably honest source of information. Read both the patient and professional versions.
To learn about the inappropriate use of androgen deprivation therapy for men with early-stage prostate cancer, click here.
Maryann Napoli, Center for Medical Consumers(c)