The largest-ever randomized trial of using the prostate-specific antigen (PSA) test in asymptomatic men over the age of 50 has found — after about 10 years of follow-up — no significant difference in prostate cancer deaths among men who were screened with a single (“one-off”) PSA test, and those who weren’t screened.
The findings come from a British study called CAP (“Cluster Randomized Trial of PSA Testing for Prostate Cancer”) published earlier this week in JAMA.
Two things caught our attention here.
First, that this “largest-ever” trial did not get large coverage in the mainstream press. In fact, none of the nearly two dozen US news outlets that we check every weekday wrote about it.
Second, it reminded us that even when coverage of screening is actually large, it often falls short in two very important ways.
Here’s what the researchers reported:
As of our publishing this article — two days after the British study was published — coverage of this “largest-ever” trial remains scant. Is it because it’s a European study? Unlikely — the results were featured prominently in one of the most prestigious US medical journals and promoted with an embargoed news release. Or, because it represents a so-called ‘negative’ or non-dramatic finding? (That is, no increase in prostate cancer deaths between the two groups found.) Who knows.
But it stands in stark contrast to the mega-coverage we’ve documented for many years on other prostate cancer screening studies that are typically much less rigorous — and which often trumpet an imbalanced, pro-screening message about prostate cancer. Not that the British study advocates against screening, but it certainly brings many of its limitations into focus.
Kenny Lin MD, a professor of family medicine at Georgetown University, was shocked that such a large study as the CAP got so little coverage. He agrees that whether a study’s results support more screening, or less screening, may have something to do with it:
“I’m amazed! Last fall there was this reanalysis of old data published in the Annals of Internal Medicine. The results supported more screening, and the mainstream news coverage was extensive. There were plenty of headlines like the LA times touting ‘prostate cancer screening saves lives after all’ (also, NYT, CBS News). Yet this CAP trial — involving 400,000 actual patients, rather than simply being an extrapolation from old data — has had virtually no coverage. And certainly no headlines stating ‘PSA screening didn’t save lives.’
“I think that journalists ought to prioritize coverage based on the quality of the study, not the perceived newsworthiness of the conclusion.”
Here are some examples of how perceived news-worthiness influences coverage of prostate cancer screening.
Every September — Prostate Cancer Awareness Month — we’re flooded with news coverage promoting mass/free PSA screenings. The intense coverage is very often fawning but rarely mentions that several reputable medical organizations don’t support such indiscriminate screenings.
And when celebrities promote screening — whether it be TV docs or the NFL — the coverage is inevitably brisk, but usually fails to bring up important considerations of over-diagnosis, over-treatment, and complications.
First, every story about screening needs to, at the very least, let readers know about the limitations of the screening method. What are the pros and cons of the test? Another way to approach this is simply asking physicians “what are the benefits and risks involved in this screening tool?”
It also helps to anticipate the questions patients might ask. Questions like: “How much can I trust a positive or negative result? (false positives/negatives) … if the test is negative, then what? … if the test is positive, what costs or risks am I exposed to if we evaluate further?” The latter are often called “downstream consequences,” and they can be significant.
In short, questions that matter to patients should matter to journalists.
Second, most cancers are nuanced diseases that exist along a spectrum of severity or aggressiveness. News coverage like that we link to above — which tends to be promotional, fear-mongering, or downright coercive — completely ignores one of the most important principles of screening. That is, the decision to get screened or not depends on a balance of benefits and risks, and how much importance the individual places on those specific benefits and risks. It is not the simple yes-or-no proposition it may appear to be. And reporters should not portray it as such.
Just as cancer is nuanced and individual, the decision to screen for it is also nuanced and individual. It requires guidance. That guidance should be balanced and complete and should involve the participation of your doctor.