This story reported on a saliva test to identify men who are at greatest risk of developing prostate cancer. The test was developed from a DNA study that identified previously unknown genetic variants common in men who had the disease. The story provided prostate cancer incidence and explained pitfalls of prostate-specific antigen, or PSA, blood tests, which have been used to screen for prostate cancer. But it misses important caveats and contains little original reporting.
A key detail the story should have included? Researchers identified genetic markers in men who were already known to have prostate cancer. They have yet to show that testing for these markers helps identify which men without prostate cancer will go on to develop it. This is an oversight we see often in news stories reporting on research about new cancer screening tests.
A test that identifies men at greatest risk of developing prostate cancer might reduce overdiagnosis and overtreatment and help some men live longer.
There’s no cost data. While this test isn’t on the market — and might never be — there are plenty of saliva-based genetic tests that are.
Says the U.S. National Library of Medicine: “The cost of genetic testing can range from under $100 to more than $2,000, depending on the nature and complexity of the test.”
This story says the test could “pinpoint the 1 percent of men who are at six times greater risk of developing the condition, and the 10 percent of men who have a threefold greater risk of developing the disease.”
But it didn’t clarify two things that are essential to interpreting this result:
The story mentioned PSA tests. which detects antigens that can be present in men without the cancer and “carries a risk of returning a false positive that can kick-start unnecessary, life-changing treatment.”
However, the story didn’t explain that a genetic test would not necessarily prevent these harms, without a better test to detect actual cancers. While men found to be at low risk might be spared additional testing, those with genetic markers for prostate cancer might be subject to more aggressive interventions that could harm them.
The story mentioned “next steps” to understand “how this could be rolled out to patients.”
But two important caveats went unaddressed:
First, it isn’t known how well these markers will predict which men will get life-threatening cancers and would benefit from aggressive prevention and treatment measures, as well as those men who can rest easy because they won’t get the disease. Other factors — such as lifestyle and environment — might influence who will and who won’t get life-threatening cancer.
Second, the study that identified these genetic markers drew on people of European descent, so it’s unclear whether the markers will apply in diverse populations such as that in the U.S.
The story grabbed our attention in the second paragraph by stating that “one in seven men in the Western world” will be diagnosed with prostate cancer in their lifetime.
Better information followed six paragraphs later:
According to the American Cancer Society, over 160,600 new cases of prostate cancer are diagnosed each year, and around 29,400 people die of the disease. The condition is rare in those below the age of 40; older men and African-Americans are most at risk. The majority of cases are caught at around 66.
The story could have done without a misleading holiday tie-in: “With Father’s Day fast approaching, use it as an opportunity to ask your dad, your brother, your uncle, your friends about their risk of prostate cancer. It’s a conversation that could save their life.”
The story would have benefited from more sources who weren’t connected to the research (both of the advocate sources were from organizations that helped fund the study). Also, most of the information wasn’t cribbed from other news outlets (in this case, the Guardian and BBC News).
The story mentioned family history as one way to flag men at greater risk of developing prostate cancer.
It mentioned PSA tests, rectal exams and biopsies as ways to test for the disease.
The story made it clear this test isn’t available but would have served readers better by explaining that higher. It stated the test “is being trialed on 300 men in doctor surgeries across London, and is due to be expanded to 5,000 next year.”
It also provided this quote: “If it is found to be effective, it could be an important tool for physicians.” [emphasis ours]
The story accurately reported that this is a “new method” of detecting risk of prostate cancer.
The story did not rely on a news release, but drew heavily from reporting by two other news organizations.