The incidence rate of lung cancer is now higher in non-Hispanic white women in the U.S. than it is in men of the same race, flipping the historical trend of a higher incidence in men, according to research published in the May 24 issue of the New England Journal of Medicine.
In a collaborative effort, researchers from the American Cancer Society (ACS) and the U.S. National Cancer Institute (NCI) examined data from the North American Association of Central Cancer Registries (NAACCR) on all types of invasive lung cancer found from 1995 through 2014 in individuals 30 to 54 years old.
They discovered that the incidence of lung cancer has decreased overall in both men and women of all races and ethnic groups. However, the greater decline in lung cancer rates in men compared with women in recent years has now led to higher relative incidence rates in women of every age group studied -- a reversal of the historic trend (NEJM, Vol. 378:21, pp. 1999-2009).
For example, the lung cancer incidence rate was 12% higher in white men than in white women 40 to 44 years old from 1995 to 1999, but it was 17% higher in women than men from 2000 to 2014.
Differences in smoking behavior likely do not explain this shift in cancer incidence because smoking prevalence among women has not exceeded that of men, lead author Ahmedin Jemal, PhD, said in a statement from the ACS. More probable contributing factors are differences in the kinds of lung cancer that affect men and women, susceptibility to the health hazards of cigarette smoking, and the reduction in risk after smoking cessation.
The authors called for continued monitoring of sex-based lung cancer risks as well as etiologic studies examining smoking-related susceptibility to lung cancer to identify reasons for the higher rates of lung cancer among young women.
