LOS ANGELES-A man with no risk factors for prostate cancer never needs to take a PSA test, according to the American Urological Association.

In a new clinical guideline unveiled Friday, the urologists said that only men between the ages of 55 and 69 should even consider getting a PSA screening test if they have no signs or symptoms of prostate cancer.

Men should get tested only after discussing all the pros and cons with their doctors, and if they decide to get tested, they should not get tested again for at least two years, the guideline advises.

The PSA test measures prostate-specific antigen. When prostate cancers develop, PSA levels in the blood can start to climb. Other conditions can also cause PSA levels to rise.

The test has been routinely used as a screen for prostate cancer starting in middle age since the 1990s.

About 16 percent of men will be diagnosed with prostate cancer in their lifetimes, and 2.8 percent will die of it, according to the National Cancer Institute.

PSA testing has been falling out of favor in recent years.

Many health experts say the test isn't very good at helping doctors figure out which men have prostate cancer that threatens their lives and which men have cancers that are so slow-growing that they're essentially harmless.

The U.S. Preventive Services Task Force said last year that PSA testing should be abandoned as a screening tool.

At the time, the American Urological Association called the advice "inappropriate and irresponsible."

The new AUA recommendations are based on medical evidence from clinical trials instead of the "consensus opinion" of urologists, as in the past.

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