Wednesday, December 05, 2012

Article by Physician Downplays Role of Smoking in Lung Cancer; Suggests that 80% of Lung Cancers Could Not Have Been Prevented by Smoking Cessation

In an article published at, Dr. Lynne Eldridge offers an intriguing argument that there has been too much of a focus on the role of smoking in the lung cancer epidemic and that anti-smoking programs can only prevent a small fraction (20%) of lung cancer cases.

Dr. Eldridge writes: "As Lung Cancer Awareness Month draws to a close I'm glowing from hearing about all of the events - and how each year there are more and more advocates investing their precious time and energy to spread awareness and provide funding for lung cancer research. But amidst that glow is a sadness. It seems just when I get excited about a new organization or another medical institution promoting awareness, I read the second line. "The key to reducing lung cancer deaths is to launch more anti-smoking campaigns." Yes, those campaigns are important. But if we want to reduce lung cancer deaths, anti-smoking campaigns just aren't going to do it. Or even come close." ...

"Nearly 80% of people diagnosed with lung cancer now, in 2012, are non-smokers. All of the anti-smoking campaigns imaginable are not going to make a difference for this 80%. Maybe a few numbers will make it even clearer. In 2008, the last year from which we have numbers available, there were 158,592 deaths from lung cancer in the United States, including 70,051 deaths in women. (Note that in the same year, there were 40,589 breast cancer deaths in women.) Using the 80% statistic, 126,874 of these deaths could not have been prevented by anti-smoking campaigns.
So why are we focusing on anti-smoking campaigns? Why are we focusing our attention on only 20% of people who develop lung cancer?"

The Rest of the Story

There is a very good reason why we are focusing our attention on the role of smoking in lung cancer. It's because smoking is the cause of approximately 80% of all lung cancer cases. Therefore, smoking is the number one preventable cause of lung cancer, and it dwarfs all other preventable causes. Focusing on the role of smoking in lung cancer makes perfect sense and to act otherwise would be irresponsible.

There is a major fallacy in Dr. Eldridge's argument. She argues that because only 20% of lung cancer cases occur among smokers, only these 20% of lung cancer cases could be prevented by anti-smoking programs. This is untrue. Among the 80% of lung cancer cases that occur among nonsmokers, the overwhelming majority - at least 75% - are attributable to smoking. These cases occur among former smokers. By hiding the fact that these lung cancer patients had a history of smoking is actually undermining the public's appreciation of the link between smoking and lung cancer. While these former smokers quit before they were diagnosed with lung cancer, it hardly means that their lung cancers were not attributable to their smoking, or that their lung cancers could not have been prevented had they not been smokers in the first place.

In fact, if anti-smoking programs were fully successful in preventing smoking, we would prevent 80% of lung cancer. According to Dr. Eldridge's argument, an 80% reduction would not represent even "coming close" to reducing lung cancer deaths.

Actually, the truth is that smoking is the number one preventable cause of lung cancer, and therefore, preventing smoking is the single most important intervention that could have the greatest impact on reducing lung cancer deaths.

I completely agree with Dr. Eldridge that anti-smoking programs alone are not the only intervention that is necessary to reduce lung cancer deaths, that attention needs to be paid to other preventable causes of lung cancer (especially radon and arsenic), and that much more money needs to be allocated to research into more effective treatments for lung cancer. However, advocating for these three causes does not necessitate undermining the well-established connection between smoking and lung cancer, nor does it justify misleading the public into thinking that only 20% - as opposed to 80% - of lung cancer cases are attributable to smoking.

I think we can be honest with the public and faithful to the basic public health science which has established smoking as the leading preventable cause of lung cancer while at the same time advocating for more attention and resources to radon and arsenic and to research into lung cancer treatment. Why the need to cut off our nose to spite our face?

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