SLOW GROWING: Prostate cancer cells (shown in a color-enhanced scanning electron micrograph) will not cause problems if left alone in most, but not all, asymptomatic men whose tumors are found after a screening test. Image: Parviz M. Pour/Photo Researchers Inc.
- Studies show that use of a blood test to screen for prostate cancer does not greatly decrease the risk of death.
- Hundreds of thousands of men have likely suffered severe side effects as a result of unnecessary treatment.
- Yet many physicians and professional medical societies believe that widespread screening saves lives.
- Screening for prostate cancer but delaying treatment in most cases may prove to be an effective compromise.
Last fall the U.S. Preventive Services Task Force dropped a bombshell, arguing that healthy men should stop undergoing a routine blood test as a screen for prostate cancer. An analysis of the best available evidence, it argued, had shown little or no long-term benefit from the measure—called the prostate-specific antigen (PSA) test—for most men with no symptoms of the disease. Use of the screening was not saving lives. In fact, it was needlessly exposing hundreds of thousands of men who were tested and found to have prostate cancer to such common complications as impotence and urinary incontinence (from surgical removal of the prostate) and rectal bleeding (from radiation treatment). Indeed, the task force estimated that more than one million men have been treated because of PSA testing who otherwise would not have been since 1985. At least 5,000 of them died soon after treatment, and another 300,000 men suffered impotence or incontinence, or both. Instead of praise for sparing more men from suffering similar fates, however, the task force’s announcement quickly drew outrage and counterarguments from several professional medical groups, including the American Urological Association.
The controversy is not new. Experts have long debated the value of the PSA test, but until now the weight of opinion in the U.S. fell on the side of doing the test. As a medical oncologist specializing in prostate cancer, however, I essentially agree with the task force’s assessment of the evidence. Most people outside the medical community do not realize how flimsy the evidence has been in favor of the screening tests. (Make no mistake, the PSA test still provides valuable information after a prostate cancer has already been diagnosed, however.) Nor does the public realize how common complications can be—even from sophisticated treatment that proponents advertise as the most advanced.