The news release reports on a journal article about a lung cancer screening initiative in the Augusta, Georgia, area. The screening initiative found that eight of 264 “high-risk” individuals — or 3 percent — had lung cancer. The release notes 3 percent is “more than double” the 1.1 percent lung cancer rate found among high-risk individuals in a national study launched in 2002.
Overall, the release provides some useful information but is unbalanced in its portrayal of screening. It cites survival statistics that inflate the true benefits of screening. And it doesn’t address a common harm of any screening test — the potential for false positive results that would lead to more invasive, stress-inducing tests.
Screening involves tradeoffs and potential harms just like any medical intervention. That’s not a message we often hear from the news media but it should be communicated more often. We explored some of the harms of lung cancer screening, including the additional invasive testing that can be prompted by false-positive results, in a recent blog post.
The release clearly states that the relevant screening technique would normally cost between $100 and $250, but was free as part of the initiative.
The release tells us how many cancers were found with the screening program, but it includes a misleading statement about what this might mean for survival rates. It notes that if lung cancer is identified in its early stages, the “overall survival rate” is 90 percent, whereas five-year survival rates for patients whose cancer is identified in the advanced stages is approximately 5 percent.
A 90% vs. a 5% survival rate sounds impressive, but this is likely a significant overstatement of the true difference. Why? As Professor Gerd Gigerenzer of the Max Planck Institute explained in a BMJ editorial, the answer has to do with something called “lead time bias.” He said, “Earlier detection implies that the time of diagnosis is earlier; this alone leads to higher survival at five years even when patients do not live any longer.”
This Youtube video by Dr. H Gilbert Welch discusses this issue in more detail. The bottom line is that when cancers are diagnosed at an earlier stage due to screening, patient survival time will be longer than if they were diagnosed later. This may or may not mean their survival was prolonged. They may have been destined to die at the same age regardless of when the cancer was diagnosed.
CT scans expose a patient to a significant amount of radiation, which this release doesn’t address at all. Do the benefits of a potential early diagnosis outweigh the risks associated with radiation exposure? That’s for each patient (and his or her physician) to decide. But a patient needs to be aware of those risks in order to make an informed decision.
In addition, an important limitation was not addressed in the release (nor was it spelled out in the study abstract). According to a 2017 article in the journal Chest, “A significant limitation of lung cancer screening is the false-positive rate. One of the major concerns with the NLST [National Lung Screening Trial] has been the high false-positive rate of screening with LDCT (27.3%).”
The release does a thorough job of laying out the screening procedure, and its rationale, for the Augusta study — and places it in the context of previous screening initiatives.
No disease mongering here, when it comes to lung cancer. However, we do have some concerns with the headline and first paragraph. More on that below in the Unjustifiable Language section.
While the story doesn’t explicitly state where the funding for the initiative came from, it’s also not clear whether there was any external source of funding. Based on the description, the study comes across as a clinician-driven initiative designed to make use of down time on diagnostic equipment. There does not appear to be a conflict of interest.
The focus appears to be on getting lung cancer screenings or not getting them — rather than on the virtues of any particular diagnostic technique (though there is one reference to the use of low-dose computed tomography (LDCT) technology rather than conventional chest X-rays). As such, we’ll rate this not applicable.
The release makes clear that the relevant diagnostic techniques are in widespread use; that there is limited access to the screening initiative (based on availability); and that there is an effort underway to expand the screening initiative.
The release makes clear that the Augusta screening initiative was modeled after a previous national study and after a similar, regional initiative in Massachusetts.
The headline states that “Free lung-cancer screening in the Augusta area finds more than double the cancer rate of previous screenings.” That’s the first thing the reader sees, and it’s a real attention-grabber. However, it is misleading. At first glance, many readers are likely to think that the rate of lung cancer in the Augusta area has more than doubled since the last time there was a lung-cancer screening initiative. That would be incorrect, given that this appears to be the first such initiative focusing on the Augusta area. Rather, the rate of lung cancer among “high risk” patients screened in the Augusta initiative was more than double that of high risk patients screened during a national screening initiative launched in 2002. That was cleared up a bit in the first paragraph. However, while the release clearly thinks this information is sufficiently important to merit making it the headline, it doesn’t give readers any information about why the cancer rate may be higher in Augusta. Even if the researchers don’t know, it’s important to just come out and say that. We urge research institutions to provide some discussion of those problems they highlight in news releases — and to take special care when writing headlines to ensure that readers don’t get the wrong idea.