Young women suffer higher rates of lung cancer than men — and scientists don’t know why.
Men were almost twice as likely as women to develop the disease in the 1980s, driven by higher smoking rates and workplace exposure to substances such as asbestos.
But with declining cigarette use and safety regulations, the pattern has changed, with young and middle-aged women now being diagnosed with the disease at higher rates than men.
There were about 65 new cases of lung cancer for every 100,000 people in 1992 and by 2019 that had dropped to about 42, according to a new report by the American Cancer Society.
Despite the progress, a gender disparity is emerging with women between the ages of 35 and 54 being diagnosed with lung cancer at higher rates than men in the same age group.
The above shows lung cancer cases among men and women divided by age groups. This shows a shift towards being more common in women in younger age groups
Scientists are not very worried – the difference is small.
There are only one or two more cases among every 100,000 women in that age group than men — but it’s significant enough that they want to know what’s causing the shift.
In their research, published in JAMA Oncologyscientists analyzed data from 22 national cancer registries covering nearly half the US population.
They analyzed data by year from 2000 to 2019, the latest year for which complete data is available.
Overall, they found that lung cancer cases have declined among both men and women over the past two decades.
But the decline was faster in men, with women aged 35 to 54 now more likely to be diagnosed with the disease than the opposite sex.
Data showed among women aged 50 to 54, the rate of lung cancer diagnosis dropped 20 percent over the study to 38.5 cases per 100,000 person-years.
By comparison, among men in the same age group the drop was 44 percent to 36.8 per 100,000.
Men were still more likely than women to be diagnosed with lung cancer in older age groups, although the gap narrowed.
For those aged 70 to 74 years old, women were 40 to 20 percent less likely to be diagnosed with the cancer than men over the study period.
Researchers, led by ACS Senior Vice President Dr Ahmedin Jemal, said: ‘We found that the higher incidence of lung cancer in women than in men has not only persisted in individuals under 50 years of age, but now extends to middle-aged adults than younger women with a high risk of the disease enter older age.
“Reasons for this shift are unclear because the prevalence and intensity of smoking are not higher in younger women compared to men, except for a slightly increased prevalence among those born in the 1960s.”
There is no evidence to suggest that cigarette smoke is more toxic to women than men and no evidence of overdiagnosis in women compared to men.
But Dr Jemal told DailyMail.com the shift could be partly down to an increase in cigarette smoking in the 1990s.
The researchers added: “Occupational exposure, which is more common in men, has decreased significantly in recent decades and may have partly contributed to the shift in disease burden.”
Lung cancer is one of the leading causes of cancer death in the United States, accounting for 238,000 cases and 127,000 deaths annually.
Lung cancer is one of the most common cancers that cause death in the US, as shown above
By sex, about 67,000 men die of lung cancer each year compared to 59,910 women.
However, deaths from lung cancer have been trending downward since the 1980s amid greater awareness of the health risks posed by cigarettes.
About 20 percent of American adults smoked in 2005, according to surveillance, but in 2021 that dropped to 11.5 percent.
In some areas of the US, such as New York City, smoking has now virtually disappeared.
It is unclear whether the vaping epidemic will increase rates of lung cancer.
But several studies now suggest that those who blow on the devices are at greater risk for the disease.
In 1980, the lung cancer rate among men was 52.4 per 100,000 people. However, for women the rate was 28.4 per 100,000.