Nobody wants to get lung cancer. Nobody who has it looks forward to the radical treatment such a diagnosis usually demands. But a recent research study lifted a bit of the dark cloud hovering over these patients. It found a significant decrease–20%–in deaths among lung cancer patients screened annually for three years with a certain type of CT scan compared with conventional chest X-rays.
This being lung cancer, and this being an evolving technology, caveats are in order: More than 90% of positive screening tests using both techniques were false positives, and the study did not assess the costs of false positive tests.
The high rate of false-positive results carries the potential for overdiagnosis and overtreatment. “Before public policy recommendations are crafted, the cost-effectiveness of low-dose CT screening must be rigorously analyzed,” Christine Berg, M.D., of the National Cancer Institute, and co-authors wrote in their discussion of the results in the New England Journal of Medicine. “The reduction in lung-cancer mortality must be weighed against the harms from positive screening results and overdiagnosis, as well as the costs.”
Approximately 157,000 Americans die from lung cancer every year; the study suggests that as many as 27,000 of them might be saved by CT screening. And although the key finding was that the technology resulted in fewer deaths, the study is notable as well for demonstrating no significantly harmful side effects. The landmark nature of the science was described by some authorities, including Dr. Otis Brawley, chief medical officer of the American Cancer society, as second in significance only to the surgeon general’s 1964 report linking smoking to lung cancer.
Critical scrutiny now shifts from “does it help?” to “who does it help and how much does it cost?” Medicare pays about $300 for a CT scan, but positive results in lung cancer patients prompt additional testing, and where that ends is anybody’s guess.
One observer casting a wary eye over not over the science but how it is represented to laypeople is Gary Schwitzer, blogging at MedPage Today. His beef isn’t solely with the unknown costs of the increased use of CT scans, but in how the media chooses to present the findings with, in his estimation, little regard for the full story. Exemplary of such shoddy coverage, he says, is a national TV broadcast network for failing to offer any discussion of false positives and cost but sparing nothing in the hyperbole department. The network, he said, called CT scans “simple,” a term with which he takes issue. Also, he said, “it cited a cost of a ‘mere $99’–not to be matched in many locations across the U.S. and failing to take into account the follow-up costs of the considerable number of false positives.”
Schwitzer claimed that the network “promoted screening advice that simply hasn’t been established and didn’t cite the source of that advice.” He said it “offered to help viewers find hospitals who could scan them–journalism or advertising?”
Raising the flag of skepticism higher in hopes that the technology’s end user–you, the patient–salutes, Schwitzer quotes Harry Demonaco, director of the Innovation Support Center at the Massachusetts General Hospital. The study, Demonaco says,”is really a tour de force that was masterfully crafted and operationalized. The authors presented the results in a well-balanced fashion. Unfortunately, the [broadcast news] report did not.
“There are 94 million smokers at risk for lung cancer in the United States today. According to the [study’s] authors, only about 7 million of them would meet the eligibility criteria to have been included in the study. This is important because the results may not be generalizable to the remaining 87 million smokers.”
Schwitzer concludes, “We know that journalists struggle with screening stories. A simple reminder may help them do a better job: All screening tests do harm; some may also do good. If you don’t reflect that in your story, you’re probably doing harm as well.”
And might we just add: Harm comes in many forms–physical, financial and emotional. As a medical consumer, we hope you try to stay abreast of developments in medicine and technology that affect you and the ones you love. Remember, like everything else, if you read or hear news about something that seems to good to be true, you might not have the full story.