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Cautious, independent voices help round out NPR’s look at experimental blood test for cancer


5 Star


Scientists Edge Closer To A Blood Test To Detect Cancers

Our Review Summary

This story is an overview of a preliminary, experimental test to screen for eight types of cancer.

Not only does this story use clear language in discussing the relevance of both false positives and false negatives in screening, it also thoughtfully includes independent sources that provide important clinical context for readers interested in understanding the limitations of cancer screening.


Why This Matters

The search for noninvasive, accurate, and affordable cancer screening is an important, emerging focus in cancer research. It’s a topic that will likely continue to generate significant media attention and, therefore, careful reporting is essential.



Does the story adequately discuss the costs of the intervention?


The story makes it clear that cost of the test is currently speculative (“could cost about $500”) and goes even further to caution that: “Johns Hopkins holds the patent and has not licensed it as yet to a company that would ultimately set the price.”

Does the story adequately quantify the benefits of the treatment/test/product/procedure?


The story makes the two key results of the test quite clear. First, that the 1,005 people tested already had been diagnosed with one of eight common cancers, and the blood test was able to detect cancer in about 70 percent of them. Second, the test was also given to 812 people without cancer and only a false reading for cancer less than 1 percent of the time.

Including the additional finding that the test was only able to detect cancer in about 40 percent of the patients with early cancer (ie. stage I) was a thoughtful way of introducing the relevant issue of falsely negative tests.

Does the story adequately explain/quantify the harms of the intervention?


The story does an excellent job of finding an independent source who explains that one of the potential risks of cancer screening tests is either identifying cancers that are not there, or are benign, and can lead to “pointless and potentially dangerous treatments.”

The opposite harm is also mentioned; that is, a screening test that erroneously gives a negative result, leading providers to falsely reassure a patient that cancer is not there.

Does the story seem to grasp the quality of the evidence?


Cautious language is used at many points in the story and it does three things quite well. First, it lists the most important limitation of the study: The screening test studied was unable to identify the type of cancer.

Second, the implications of both falsely positive and falsely negative tests were explained succinctly and placed in a clinical context that would matter to those undergoing screening.

Finally, we were very encouraged by the inclusion of this sentence: “… the researchers will still have to demonstrate that the test improves and extends the lives of cancer patients.”

Does the story commit disease-mongering?


There is no disease mongering in this story.

Does the story use independent sources and identify conflicts of interest?


The two independent sources cited provide important context for understanding the strengths, limitations, and clinical context of the screening test.

Does the story compare the new approach with existing alternatives?

Not Satisfactory

This was a tough call, but ultimately we felt the story would have been stronger had it mentioned the performance of current screening methods for some of the cancer types, such as Cologuard for colon cancer. That said, we were glad the story included some of the pitfalls of screening for prostate and breast cancer, as well as the long struggle to develop more blood tests for cancer.

Does the story establish the availability of the treatment/test/product/procedure?


It’s mentioned the authors of the study are “hoping their idea would eventually lead to a $500 test … but they have a long way to go.” Future studies of the screening test are also discussed, so it seems clear this test is not currently available.

Does the story establish the true novelty of the approach?


It’s made clear that “there have been many attempts over the decades to develop blood tests to screen for cancers … but these methods don’t give reliable results.” It’s also pointed out that what makes this screening test unique is that it combines two previously used methods (screening for proteins and for DNA) into one test.

Does the story appear to rely solely or largely on a news release?


This story does not appear to rely upon a news release.

Total Score: 9 of 10 Satisfactory


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