Is the PSA Test Right for You?

Nothing sparks more controversy in the urologic world than the PSA test. PSA is a blood test used in men to screen for prostate cancer. The higher the PSA, the greater the probability of finding prostate cancer on biopsy. The trouble is that we often found small volume, less aggressive cancers that never needed treating, and then treated them anyway. That is overtreatment, and it does real harm.

I wrote the first version of this post in 2014, back when the official recommendation was not to screen at all. Quite a bit has changed since then, and most of it has moved in a direction that makes the test more useful rather than less.

The arguments against checking your PSA

• A large share of older men have some form of prostate cancer that would never have troubled them. Autopsy studies have found it in a substantial percentage of men over 70.

• Only a minority of men with prostate cancer die from it.

• There are real risks to a prostate biopsy, including bleeding, infection and discomfort.

• Being told you have cancer costs something, even when that cancer is low risk. The anxiety is not nothing.

• Screening finds disease that would never have surfaced on its own. That is overdiagnosis, and it was a fair criticism.

What has changed

Three things, and together they answer most of the objections above.

The first is active surveillance, and it is the big one. When a man is diagnosed with low risk prostate cancer today, the usual recommendation is not surgery or radiation. It is careful monitoring, with periodic PSA, imaging and repeat biopsy when indicated, and treatment held back for the cancers that show they need it. The overtreatment problem that drove the case against screening was mostly a treatment problem rather than a testing problem. The treatment side is what got fixed.

The second is MRI before biopsy. Instead of sending every elevated PSA straight to a systematic biopsy, we image first. That lets us skip the biopsy in some men, aim at the suspicious area in others, and find fewer of the insignificant cancers that caused the overdiagnosis complaint in the first place.

The third is the recommendation itself. In 2012 the U.S. Preventive Services Task Force gave PSA screening a grade D, recommending against it for all men. In 2018 that was revised to a grade C for men aged 55 to 69, which means the decision should be an individual one made with your physician. For men 70 and older it is still a grade D. So the blanket "don't screen" advice that shaped the original version of this post is no longer where things stand.

The arguments in favor

• Prostate cancer is still one of the leading cancer killers of men in America.

• Since we started checking PSA, the death rate from prostate cancer has fallen by roughly half. More recent numbers show an increase in mortality, and an increase in men presenting with later stage disease, because they were not screened at a younger age.

• Over that same period the death rate among men already diagnosed with metastatic disease did not improve nearly as much. That points to early diagnosis as the source of the gain.

• Screening studies with more than ten years of follow up do show a survival benefit.

• Since screening rates dropped after 2012, the rate of men showing up with advanced, already spread disease has been climbing. That is exactly what you would predict if you stopped looking.

Common sense still applies

Data and statistics can be manipulated to show almost anything you want. The short term U.S. screening study was roughly the equivalent of taking a thousand twenty year old men, having half of them smoke for five years, and then concluding from the fact that nobody had died of lung cancer or heart disease that tobacco is harmless. Does that make it true? No. It means the study was too short to answer the question it was asked.

Where that leaves you

PSA is a tool. It needs to be understood, not abused and not abandoned. Yes, it has been overused. Yes, prostate cancer was over treated. Those were problems to learn from rather than turn away from, and for the most part we have.

For most men, screening every one to two years from about age 50 to 69 is reasonable. Men at higher risk should start earlier, and that includes men with a family history, African American men, and men with a known genetic risk. Men in good health with a life expectancy beyond ten years can reasonably keep checking past 69. Men who are unlikely to live another decade generally gain nothing from it.

This should be a shared decision between you and your doctor. I know that sounds like a dodge. It isn't. The right answer really does depend on who you are, and anyone who gives you a single answer for every man is not paying attention.