Lung cancer and tobacco-linked mortality rates are expected to decrease by 63% well into the next half-century, largely due to tobacco prevention and cessation efforts over the last five decades, according to the findings of a comparative simulation study published in the Annals of Internal Medicine.
Although lung cancer is still the leading cause of cancer-related death among men and women in the United States, lung cancer mortality has significantly decreased since the 1990s due, in part, to the rise of anti-smoking policies and activism—particularly anti-smoking ads that became widely popular during the Clinton Administration, thanks in large part to the Tobacco Settlement Agreement of 1998.
At that time, well-known cigarette ads were ironically transformed to promote anti-smoking campaigns that actively called for the boycotting of both cigarettes and the marketing of cigarettes to children. Other ads used the gruesome portrayal of diseased organs to demonstrate the real-life health effects of smoking and thus encourage abstinence among non-smokers.
Experts project that smoking and tobacco-related diseases will continue to decrease in the coming years. However, the precise impact that existing anti-tobacco policies will have on future smoking and smoking-related outcomes—especially lung cancer burden—is unclear. Thus, the authors of this simulation study aimed to estimate reductions in tobacco use and lung cancer mortality from 2015 to 2065 as affected by current tobacco control efforts.
The researchers used a comparative modeling approach with a “status quo” premise, assuming that no new changes to tobacco control efforts will occur and that rates of smoking initiation, smoking cessation, and smoking intensity (cigarettes/day) will remain consistent, especially by birth cohort.
Under this status quo premise, all models reliably predicted a considerable decrease in lung cancer mortality from 2015 to 2065. Specifically, age-adjusted lung cancer mortality was estimated to decrease by 79% between 2015 and 2065, and the number of deaths attributable to lung cancer was projected to decrease from 135,000 to 50,000 (a 63% reduction) during the same time period.
Interestingly, according to the results of the study, the current disparities between lung cancer prevalence by sex will cease to exist by the mid-2040s, when rates between men and women will converge and become relatively equal.
Moreover, as past cohorts that represent higher smoking rates (eg, persons aged 54 years or older) gradually die, the prevalence of smoking will significantly decrease. This is largely attributed to the fact that older cohort members were introduced to smoking prior to the famous 1964 Surgeon General’s Report on smoking. The continued reduction in lung cancer mortality is expected to occur due to lower initiation rates among younger cohorts in the first place.
Lung cancer screening
Although this study showcases an optimistic perspective towards the future of lung cancer, the model equally predicts that, under status quo trends, 4.4 million lung cancer deaths will still occur from 2015 to 2065. Most of these deaths will be attributed to smoking.
The study highlights that, while we can rely on past efforts to help combat lung cancer in smokers, more still needs to be done. In particular, efforts that address lung cancer screening should be at the forefront of cancer research since this will further reduce the burden of lung cancer and promote early treatment.
Limitations of status quo assumptions
In assessing the results of this study, keep in mind that the status quo premise that underlies the simulation models doesn’t consider other positive effects that may also contribute to the reduction in lung cancer mortality. Current changes to control tobacco use are very real and noteworthy. For example, the introduction of e-cigarettes and current goals of regulating the level of nicotine in cigarettes may become useful influencers in the future of lung cancer prevalence.
In response to the data presented in this research, Richard Rosen, MD, Cone Health, Greensboro, NC, commented on the status quo approach in a letter to the editor in the same issue: “Although an ounce of prevention may be worth several pounds of cure when it comes to lung cancer, the authors do not consider potential progress in the treatment of this condition in the next 50 years.”
Dr. Rosen emphasized the impact that advancements in lung cancer treatment will have on reducing mortality. In particular, he pointed to the role of targeted therapy on molecular subgroups for improving lung cancer survival. Dr. Rosen argued that, while prevention will continue to be the primary strategy against lung cancer, advances in treatment will also improve survival odds.
Overall, the investigators of the current study highlighted the importance and power of current tobacco control efforts. Should these trends remain consistent, there will be notable reductions in the lung cancer burden in the United States in the next 50 years. If anything, this study emphasizes the power of what is to be expected if additional policies, preventative measures, and treatment advances join together in taking down lung cancer.