0

PSA test overused, but helpful for at-risk men

Dr. Samir Khleif

Dr. Samir Khleif

In May, the U.S. Preventive Services Task Force, an independent group of national experts that provides evidence-based recommendations to improve Americans' health, made an announcement that was widely debated by cancer communities and men everywhere.

The announcement was this: The U.S. Preventive Services Task Force recommends against prostate-specific antigen (PSA)-based screening for prostate cancer. The potential benefit does not outweigh the expected harms.

A simple blood test, the PSA screening, combined with a digital rectal exam, has been relied on for the past two decades as an easy method to evaluate men's risk for prostate cancer, although its accuracy and efficacy for decreasing the risk of prostate cancer death has long been a matter of debate. This announcement understandably caused confusion, doubt, even anger among men in general and prostate cancer survivors in particular.

But, it's an announcement that perhaps has been a long time coming.

What the task force really found is that too many of us have been relying too much on the PSA test. As a screening tool, it has always been somewhat controversial.

The PSA test frequently leads to the detection of slow-growing, non-life-threatening prostate cancers (referred to as "overdiagnosis"), putting men at risk for more invasive tests and unnecessary therapies that can cause pain and health problems. In addition, many other factors besides cancer can raise PSA levels, including infection, certain medications and a benign enlargement of the prostate that often occurs with age. As a result, about 100 to 120 out of every 1,000 men screened will receive a false-positive test -- in other words, the test may suggest they have cancer when in fact they don't. This can cause anxiety and worry. It can also lead to other tests, including invasive biopsies that surgically remove tissue samples and may cause complications like infection (which may sometimes be life-threatening), bleeding, urinary problems and pain.

The PSA test can also lead to overly aggressive treatment. The fact is, most prostate cancers -- nearly 63 percent -- occur in men 65 and older. Because most prostate cancers are slow-growing, these men will more likely die from old age or other health problems than from this type of cancer. But, since there's also no sure way to tell which cancers are aggressive, many men choose to receive invasive treatments that often lead to permanent urinary and sexual dysfunction.

So what should men do? Certainly, the PSA test has been overused. But, it can be helpful for men in certain risk categories. These categories include men 50 or older who:

-- Have one or more first-degree relatives (a father or brother, for example) who were diagnosed with prostate cancer before age 60;

-- Have one or more first-degree relatives who died of prostate cancer before age 75.

Still, even in these men, it is important to note that it remains unproven whether any benefits of screening outweigh the harms.

However, a more personalized approach to screening will help target men who should more concerned about their risk of prostate cancer. And based on the test results, physicians can also talk to men about their options. Not all men with prostate cancer may need cancer treatment right away. Careful periodic monitoring for signs of cancer progression might be the best first step.

Finally, the task force's recommendation underlines how important it is for all of us to be informed about the benefits and risks of any screening test. Some men may still opt for the screening after their physician has carefully explained the potential risks and benefits.

Dr. Samir N. Khleif, director of Georgia Health Sciences University Cancer Center, has more than 22 years of experience in cancer research and treatment, including in the Cancer Vaccine Section at the National Cancer Institute. The GHSU Cancer Center is working toward becoming Georgia's second National Cancer Institute-designated cancer center.