Mass prostate cancer screening catches more tumors, doesn't reduce deaths
Annual prostate cancer screening is shown in a new study to have no benefit for reducing deaths from the disease. The newest study looked at men ages 55 to 74 who received a PSA tests for six years, digital rectal exam for four years, or prostate cancer testing only if a physician recommended it.
The finding showed that only young men – those who are likely to live longer – would benefit from getting a PSA test each year. The reason, say the researchers, is because “A large majority of the cancers we found are slow-growing tumors that are unlikely to be deadly."
Lead author and principal investigator Gerald Andriole, MD, chief urologic surgeon at the Siteman Cancer Center at Barnes-Jewish Hospital and Washington University School of Medicine explains most men just don’t need to be screened annually.
The study, which included 76,000 men, showed checking for prostate cancer annually didn’t lower death rates from prostate cancer, but it did lead to more prostate cancer diagnoses.
"Now, based on our updated results with nearly all men followed for 10 years and more than half for 13 years, we are learning that only the youngest men — those with the longest life expectancy — are apt to benefit from screening. We need to modify our current practices and stop screening elderly men and those with a limited life expectancy," says Andriole. “Instead, we need to take a more targeted approach and selectively screen men who are young and healthy and particularly those at high risk for prostate cancer, including African-Americans and those with a family history of the disease."
His recommendation is that men get a baseline PSA in their early 40’s. If levels are low, the chances of prostate cancer later on are low. For young men whose PSA level is elevated, repeat testing would be prudent.
In the study, the was little difference in death rates for men who had annual prostate cancer screening and those who had routine care at the doctor’s office – 158 men died from the disease who had their annual PSA and 145 deaths were found among men who were only screened with physician recommendation.
PSA testing discovered 12 percent more prostate cancer tumors, compared to men receiving routine exams.
Men who were diagnosed with prostate cancer were more likely to die from other causes, such as heart and liver disease, stroke or diabetes, also found in the Prostate, Lung, Cancer, Colorectal and Ovarian (PLCO) Cancer Screening Trial.
Virginia Moyer, MD, task force chair and professor of pediatrics at Baylor College of Medicine in Houston, supporting the notion that over screening for cancer can be deleterious, wrote in the December 2011 journal of the National Cancer Institute:
“The public thinks once you have a cancer cell in your body, it will progress predictably and inevitably to a terrible death. That is simply not true of most cancers. It’s certainly not true of prostate cancer, not true of breast cancer, not true of most skin cancers, not true of all cervical cancers. You have a disease that is highly variable. Knowing you have cancer cells in your prostate or breast doesn’t mean that, unless you do something radical, you’re going to die of that. A significant proportion of people whose disease is detected by screening never would have known about their disease in their entire lifetime. A good proportion would have died of something else before the cancer progressed to being clinically significant, and many would have died of old age.”
Andriole also says past findings show that screening for prostate cancer on a regular basis can lead to unnecessary treatments that negatively impact men’s health from urinary incontinence and impotence, including surgery and radiation treatment.
He says it’s time to take a more individualized approach to prostate cancer screening, that doesn’t rely on age alone, “…to determine which men should be screened with PSA in the first place, how frequently they should be tested, the PSA level at which they should be biopsied and whether their cancer warrants aggressive therapy."
The study takes a closer look at the benefits and risks of annual prostate cancer screening, based on age. The study found annual PSA testing doesn’t reduce the number of deaths from prostate cancer, but it does lead to more tumors being diagnosed.
JNCI J Natl Cancer Inst (2012)doi: 10.1093/jnci/djr500
Andriole GL, Crawford ED, Grubb RL, Prorok PC et al.
“Prostate cancer screening in the randomized prostate, lung, colorectal and ovarian cancer screening trial: mortality results after 13 years of follow-up.”
Jan. 6, 2012.
JNCI J Natl Cancer Inst (2012)104 (1): 8-9.doi: 10.1093/jnci/djr539
“New PSA Guidelines Discourage Overscreening”
December 14, 2011
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