After about 10 years, PSA-based screening results in small or no reduction in prostate-cancer-specific mortality and is associated with harms related to subsequent evaluation and treatments, some of which may be unnecessary."

The main problem with the PSA test is that it can't distinguish a slow-growing and probably harmless cancer from a fast-growing and deadly one, leading to unnecessary and aggressive treatments.

So you go from being a guy who feels fine and who is potentially one of the majority who would never have known they had this disease to being a guy who wears adult diapers.

"The PSA test is hardly more effective than a coin toss," wrote the discoverer of the PSA in the New York Times, calling the test a "hugely expensive public health disaster … The medical community must confront reality and stop the inappropriate use of PSA screening. Doing so would save billions of dollars and rescue millions of men from unnecessary, debilitating treatment."

If you're a candidate for testosterone replacement therapy (TRT), it's reasonable to do a PSA test, to make sure you don't have preexisting prostate cancer. And it's reasonable to do a PSA test three to twelve months after starting TRT.

Otherwise, PSA should not be done routinely. Also, be careful to decrease the risk of false positives by not having a PSA test within 24 hours of having a rectal exam or colonoscopy.