Lindi Campbell vividly remembers the date: Dec. 6, 2017. That was the day she received the heartbreaking news – she had lung cancer. “I was completely shocked,” she says. Despite being a non-smoker and not knowing anyone else with lung cancer, especially a “never-smoker” like her, she felt completely isolated.
Determined to not only take care of herself, but also to connect with others who could understand her experience, she took action. A year after her diagnosis, she founded Breath of Hope Kentucky, a nonprofit lung cancer advocacy and outreach group.
Her efforts led her to meet more than 20 never-smokers from her state, and she noticed something surprising – only one of those individuals was male.
This discrepancy brings to light an intriguing pattern that has left scientists perplexed: Why are women significantly more likely than men to get lung cancer if they never smoked?
While cigarette smoking is the leading cause of lung cancer, approximately 15% to 20% of cases in the U.S. occur in never-smokers – individuals who have either never smoked or have smoked fewer than 100 cigarettes in their lifetime.
In the U.S., about 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.
Given that cancer is typically more prevalent among men, this statistic stands out as an anomaly. “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.
Notably, anyone can get lung cancer due to factors like exposure to secondhand smoke and environmental pollutants. For instance, Dana Reeve, the wife of the late actor Christopher Reeve, died of lung cancer at age 44, despite never having smoked. Her stage IV cancer, which was discovered after an X-ray for a persistent cough, serves as a powerful example of the enigma surrounding lung cancer among non-smokers.
The reasons behind this phenomenon are complex and still not fully understood. Factors such as differences in the immune system between women and men, gene variants, hormones, and environmental elements like air pollution may all contribute to the gender disparity in never-smokers with lung cancer, Berger explains.
While the research is still in its early stages, it’s clear that a combination of factors may be at play. Despite being a non-smoker, Campbell believes she developed lung cancer due to her exposure to secondhand smoke. “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,” she reveals.
Remarkably, lung cancer tumors in never-smokers are often different from those found in smokers. “There are distinct differences in the immune landscape,” says Ramaswamy Govindan, MD, a professor of medicine at Washington University in St. Louis.
Furthermore, the vast majority of never-smokers with lung cancer have a “targetable” gene change or biomarker. These distinctions in tumor characteristics provide valuable insight into potential treatments and management strategies for the disease.
