Lindi Campbell can still remember the exact date: Dec. 6, 2017, was the day she found out she had lung cancer. “I was so shocked,” she says. Not only had she never smoked, but she also didn’t know anyone else who had lung cancer, especially not “never-smokers” like herself. This made her feel incredibly isolated.
Instead of just focusing on her own health, she decided to reach out to others who could relate to her experience. A year after her diagnosis, she established Breath of Hope Kentucky, a nonprofit organization dedicated to advocating for and supporting lung cancer patients.
Since then, Campbell has connected with over 20 never-smokers in or from her state. She also noticed something unusual: of those people, only one is male.
This gender imbalance is just one example of a larger trend that has puzzled scientists for years: Why are women much more likely than men to get lung cancer if they never smoked?
While smoking is the primary cause of lung cancer, about 15% to 20% of cases in the U.S. occur in never-smokers, who are individuals who have either never smoked or smoked fewer than 100 cigarettes in their lifetime.
At least two-thirds of lung cancer cases in never-smokers are women, according to Alice Berger, PhD, a laboratory researcher at the Fred Hutchinson Cancer Research Center in Seattle.
“In the last 5 years, there’s been a lot of attention on, Why is this happening? And why are women disproportionately affected?” Berger says.
The reasons behind this phenomenon are still not fully understood. It may be due to variations in the immune systems between men and women, Berger explains. Other factors being investigated include gene variants, hormones, and environmental factors like air pollution or radon.
“But that research is still in the early stages,” Berger says, indicating that a combination of factors might be involved.
Even though Campbell wasn’t a smoker, she was exposed to secondhand smoke while growing up. “I grew up in a home of smokers. There were nine people, and only two of us had never smoked. I was the youngest and the only one who got lung cancer.”
Lung cancer tumors in people who have never smoked often have distinct differences from those in smokers, explains Ramaswamy Govindan, MD, a professor of medicine at Washington University in St. Louis.
For example, 78% to 92% of never-smokers with lung cancer have a “targetable” gene change or biomarker. This marker may respond to an FDA-approved drug,