Prostate cancer: Test or no test?

By MultiCare Health System
It's a simple blood test that can help detect a common cancer well before any symptoms. Yet the prostate-specific antigen test, or PSA, remains controversial.
Men should not undergo this test without first discussing it with their healthcare providers.
To understand why, MultiCare Health System urologist Douglas Sutherland says you need to understand both the test itself and the disease it's designed to detect – prostate cancer.
“It is not invasive at all,” Sutherland said of the PSA screening.
Unlike a colonoscopy or a mammogram, it doesn't require any additional procedures or preparation, Sutherland said. Consequently, it is often added to routine annual labs without the patient even knowing about it.
And yet five years ago, the U.S. Preventive Services Task Force, the government committee that advises Medicare, gave the PSA a D grade, meaning they recommended against it.
This year, as part of its routine evaluation cycle, the task force is expected to raise the grade back to a C for men ages 55 to 70. A C means they recommend that physicians offer the test in select cases based on their discretion and patient preference.
According to Sutherland, the task force recommendation comes, in part, because the test can't actually detect cancer.
“The PSA blood test can only provide an estimate of risk for a given man,” he says. “And we now know the PSA test is very inaccurate.”
There is a significant rate of “false positives” in which high PSA levels indicate potential cancer when there is none. Still, we're talking about cancer, so false positives probably seem like a small price to pay for potentially catching the disease early, right?
That's not necessarily true, Sutherland said, for two reasons. The first is that the next step is much more invasive and unpleasant. If a man has a high PSA level, he must undergo a prostate biopsy to be sure. The procedure only takes about five minutes and carries a small risk of bleeding and infection. But for most men, that's not the worst part.
“It is considered very uncomfortable,” Sutherland said.
But if you find prostate cancer, that makes it worthwhile, right? That's the second reason routine PSA screening isn't the standard of care. Not all prostate cancers are equal, and in fact, most are slow-growing and unlikely to cause any problem.
But once discovered, many men will choose to treat their cancer. And with slow-growing prostate cancer, the cure can be worse than the disease.
“They will suffer all of the consequences of the treatment – such as sexual and urinary dysfunction – with no benefit,” Sutherland said of men who discover slow-growing, “harmless” prostate cancer as a result of routine screening.
Whether someone should get the PSA screening “really depends on the individual man and his specific goals,” Sutherland said. While most men develop prostate cancer late in life when the slow-growing disease simply doesn't have time to cause problems, the doctor noted that “for young, healthy men, with a long life expectancy, an earlier diagnosis is in fact a life-saving event.”
Sutherland said it is “most critical” that men discuss their individual risk factors with their doctor and make an informed decision about whether or not to have a PSA screening.  
“Those at highest risk for developing serious prostate cancer are men with a first-degree relative with prostate cancer (father, brother) and those men of African descent,” he said.
Lifestyle also seems to be a factor, with obesity, high-fat diets, smoking and lack of exercise associated with more aggressive forms of prostate cancer, although the direct cause-and-effect isn't known.
Testosterone-replacement therapy has been feared by some to potentially cause or worsen prostate cancer, but “this concern is increasingly felt to be inaccurate,” Sutherland said.

MultiCare Health System is a not-for-profit health care organization with clinics and hospitals in Pierce, King and Kitsap counties. In south Pierce County, clinic locations include Eatonville, South Hill, Spanaway and Frederickson.


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