This story reports on the results of a new study evaluating the effectiveness of prostate-specific antigen (PSA) testing in men with BRCA gene mutations. In preliminary results, the study found that PSA testing was more likely to find cancers in high-risk men than average-risk men. Whether simply finding more cancers would lead to better outcomes in terms of survival remains unclear.
This story adequately describes the novelty and availability of PSA testing and does not engage in disease mongering. It does a good job of describing the potential harms of PSA testing and of quantifying the possible benefits. The story could have been improved by more fully describing the importance of these findings, quoting an independent expert and describing the costs of the test.
The PSA screening controversy endures because of the absence of convincing evidence that PSA screening produces more good than harm for men. The harms are known – overdiagnosis and overtreatment. The harms of finding and treating harmless cancers are incurred in the near term. The benefit in terms of mortality reduction potentially realized down the line is small if at all. Over the years there have been myriad strategies suggested to improve the diagnostic performance of the PSA test. The problem is that even if one improves on the operating characteristics of the PSA test, in this case by targeting a select "high risk" population (such as those with BRCA mutations), we still will not know if early detection and aggressive treatment of prostate cancer in this population of men reduces mortality sufficiently to offset the known harms incurred. That question would need to be answered by additional research.
The story makes no mention of the costs of the test, associated follow-up procedures or the tests for BRCA mutations.
The story reports the results in a way that is typically rare in journalism – using the positive predictive value of the test. This is a much more helpful way to present the information to consumers than other measures commonly used in screening tests, such as sensitivity/specificity. At the same time, the heart of the PSA screening controversy remains. Even if one improves on the performance of the PSA test to detect more prostate cancers early, we still don’t know if the potential benefits in terms of mortality reduction outweigh the known harms of overdiagnosis and overtreatment. The ability to one day differentiate the indolent prostate cancers from the aggressive cancers will be key. This study did not do that, despite the comments from the author.
The story mentions several important potential drawbacks of PSA screening and correctly points out that many European countries do not routinely screen for prostate cancer. It also includes some important context, noting "a study in the United States last year found that routine prostate cancer screening had resulted in more than a million being diagnosed with tumors who might otherwise have suffered no ill effects from them."
The story adequately describes the current study, but it could have done more to describe the strength of these findings. It does note, for example, that the story is reporting on initial findings, with a small sample size. "The ICR-led study is aiming to find out whether screening men who have genetic variants that increase their prostate cancer risk could lead to earlier diagnosis. It aims to screen 1,700 men for five years, but results from the first 300 men were published in the British Journal of Urology International." It does not, however, make clear whether the cancers found would go on to cause a problem. The story also allows the study’s lead author to say "the findings added to the increasing evidence that BRCA gene variation carriers develop more aggressive disease and supported the idea that men with genetic risks should be routinely screened for prostate cancer." By our reading of the study, this appears to overstate the findings.
The story does not exagerate the seriousness or prevalence of prostate cancer.
A major problem with this story is that it only quoted one expert who is one of the researchers on this study, and all comments from him appear to be from the press release. The story could have been greatly improved by quoting another expert who could have provided some valuable perspective on the importance of these results.
The story mentions no screening and population-wide screening as alternatives.
The story makes it clear that PSA testing is the standard screening for men, saying, "U.S. doctors routinely recommend PSA screening in men over 50 on the assumption that early diagnosis and treatment is better than doing nothing."
Clearly PSA screening is not a new idea, however screening higher risk men based on BRCA mutations is relatively new. This story makes that clear.
Most of the information in the story about the study appears to come from this press release, including the sole quote: "Although these are early results, it appears that PSA screening is reasonably accurate at predicting potentially aggressive prostate cancer among men at higher risk of the disease due to a genetic predisposition. This study provides support for continued screening in men with genetic mutations." While the story does add some great context about screenings and previous studies, it is hard to overlook this dependence on a press release.