New study adds to changing picture of who develops lung cancer
A new study has found that a growing proportion of people diagnosed with lung cancer had never smoked, adding to evidence that the traditional picture of lung cancer no longer reflects everyone affected by the disease.
Researchers analysed 5,131 people with non-small cell lung cancer (NSCLC) treated between 2005 and 2024. They found that the proportion of people diagnosed who had never smoked increased from 12.3% in 2005 to 18.0% in 2024.
The study also found that people diagnosed with lung cancer who had never smoked were more likely to be women, people under 50, people over 80, Black people and Hispanic people. The largest increase over time was seen among Hispanic women.
Although the research was carried out at a single cancer centre in the United States, it adds another important piece to a much wider picture that is emerging from lung cancer research.
Smoking remains the biggest risk factor for lung cancer, and reducing smoking is one of the most effective ways to lower the risk of developing the disease. However, not everyone who develops lung cancer has a history of smoking. Increasingly, research is showing that lung cancer affects a broader range of people than many assume.
A growing proportion of people diagnosed had never smoked
The researchers reviewed medical records from more than 5,000 people diagnosed with NSCLC over almost two decades.
Overall, 715 people (13.9%) had never smoked.
Looking at changes over time, they found that the proportion of diagnoses in people who had never smoked increased steadily from 12.3% to 18.0%, representing a statistically significant annual increase.
After adjusting for other factors, people who had never smoked were significantly more likely to be:
women
younger than 50 years
older than 80 years
Black
Hispanic.
The researchers suggest these findings support continued work to develop approaches to identifying lung cancer risk that consider factors beyond smoking history alone.
Importantly, the study examined the proportion of people diagnosed with lung cancer who had never smoked within this group of patients. It does not show that the overall incidence of lung cancer in people who have never smoked has increased across the wider population.
Another piece of a bigger picture
This study does not stand alone.
Over the past two years, several studies have challenged long-held assumptions about who develops lung cancer.
Research has highlighted the growing recognition of lung cancer in people who have never smoked, increasing concern about early-onset lung cancer in younger adults, and important differences in how lung cancer affects women.
Taken together, these findings suggest that our understanding of lung cancer is becoming more nuanced.
Lung cancer is not a single disease with a single cause. Different genetic alterations, environmental exposures and biological factors all contribute to risk. Researchers are continuing to investigate why some groups appear to be represented more frequently than expected and what this could mean for prevention, diagnosis and treatment.
Challenging assumptions
Many people still think of lung cancer as a disease that mainly affects older people with a history of smoking.
That perception can contribute to stigma and may influence how people interpret persistent symptoms or their own risk.
Awareness needs to reflect what the evidence is showing.
Smoking remains the biggest risk factor for lung cancer. At the same time, it is important to recognise that anyone can develop lung cancer, including people who have never smoked.
A better understanding of who develops lung cancer could help improve awareness, support research into additional risk factors and inform future approaches to identifying people who may benefit from screening.
What happens next?
This study does not change current lung cancer screening recommendations.
However, it adds to ongoing research exploring whether future approaches to assessing lung cancer risk should consider a wider range of factors alongside smoking history.
Further studies in larger and more diverse populations, including across Europe, will be important to understand whether similar patterns are being seen elsewhere.
As evidence continues to grow, one message is becoming increasingly clear.
Lung cancer can affect anyone. Understanding that is an important step towards reducing stigma, encouraging earlier diagnosis and ensuring that people who develop lung cancer are not overlooked because they do not fit traditional assumptions about the disease.
Sources
Ha G, Vimolratana M, Chudgar NP, et al. Brief Report on Sociodemographic Patterns of Lung Cancer in Individuals Who Never Smoked. Clinical Lung Cancer. Published online 2 July 2026.