Wednesday, October 6, 2010

JAMA’s Breast And Ovarian Cancer Article: Getting The Facts Straight

Gary Schwitzer's <a href='http://keep-health-work.blogspot.com/' target='_blank' class='infotextkey'>Health</a>NewsReview Blog

Journalist Andrew Holtz has been a colleague for longer than probably either one of us wants to remember. He is currently one of our story reviewers on HealthNewsReview.org. In fact, he was one of the reviewers on four stories we analyzed last week on the same study. He thought there were some important take-home messages that rose above the walls of our formal systematic review, so he wrote this guest blog post, and we thank him for it:


The Sept. 1 issue of the Journal of the American Medical Association included an article that is likely to have a strong influence on the advice given to women who have a very high risk of breast and ovarian cancer linked to mutations of the BRCA1 and BRCA2 genes. Of the four stories we reviewed, only the AP report scored well on our review criteria.


I know what my first journalism professor, Marion Lewenstein, would have done with at least two of the stories: Given them an “F” for factual errors without further consideration of their merits.


The NPR story stated that the study “tracked nearly 2,500 women with the BRCA mutations who had surgery to try to prevent breast and ovarian cancer.” (emphasis added) While the study did indeed include nearly 2,500 women with BRCA mutations, 38 percent had their ovaries removed and only 10 percent had preventive mastectomies. The Reuters report not only committed the same error in describing the participants in the study, it also confused the relative risk of cancer with the women’s lifetime risk. For instance, the story said, “Women with mutations in the BRCA1 or BRCA2 genes have a 56 to 84 percent higher risk of developing breast cancer during their lifetimes.” (emphasis added) Actually, those figures are estimates of the absolute lifetime risk; that is, half to more than three-quarters of these women would be expected to develop breast cancer. That risk is several times higher than the commonly quoted figure of a 12 percent lifetime risk for women in general.


It is hard to put much faith in the rest of the reporting when a story contains such blatant errors. The news organizations should not only publish corrections, but also review their procedures to reduce the likelihood of such embarrassing gaffes.


The stories also included some troubling quotes. While journalists are not always experts, we have a responsibility to do the best we can to evaluate what experts tell us and put the quotes in context with other information.


The NPR story included a quote from a researcher that claimed mastectomy reduced the risk of death. That’s not what the study reported. Women who had their ovaries removed were less likely to develop cancer and less likely to die. The women who had their breasts removed did not develop breast cancer during the study period, but there was nothing in the study about mastectomy reducing the risk of death. Even if the expert said the words, the reporter should have known that the study did not report that finding.


The Reuters story also failed readers by allowing an expert to urge (without any challenge or context) “all women with a family history of early breast cancer” to have genetic testing. That advice goes far beyond what other experts say. It is quite easy to look up an online risk calculator that will tell you that less than 3 percent of women who have a single relative who had early breast cancer carry the BRCA gene mutations. That prevalence is only 1 percent higher than that among women with no family history of breast or ovarian cancer. (The rates for women of Ashkenazi heritage are higher.) Why would gene testing not be routinely recommended for women with no known risk factors (and a 1.5 percent risk of carrying a BRCA mutation), but then if the risk rises to 2.6 percent, suddenly testing should be universal? The reporter should have asked that question and given readers at least some of the background.


This study of cancer genetics and preventive surgery is newsworthy. All of the news organizations that covered it should have invested the care, attention and skill shown by the AP.


- By Andrew Holtz


We welcome any comments on our story reviews or on Holtz’s guest post.



                       

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