Abstract
Background
Lung cancer clinical guidelines and risk tools often rely on smoking history as a significant risk
factor. However, never-smokers make up 14% of the lung cancer population and this
proportion is rising. Consequently, they are often perceived as low-risk and may experience
diagnostic delays. This study aimed to explore how clinicians make risk-informed diagnostic
decisions for never-smokers.
Methods
Qualitative interviews were conducted with ten lung cancer diagnosticians, supported by data
from interviews with twenty never-smoker lung cancer patients. The data was analysed using
framework analysis based on the Model of Pathways to Treatment framework and data-driven
interpretations.
Results
Participants described three main strategies for making risk-informed decisions incorporating
smoking status: guidelines, heuristics and potential harms. Clinicians supplemented
guidelines with their own heuristics for never-smokers, such as using higher thresholds for
chest x-ray. Decisions were easier for patients with high risk symptoms such as haemoptysis.
Clinicians worried about over-investigating never-smoker patients, particularly in terms of
physical and psychological harms from invasive procedures or radiation. To minimise
unnecessary anxiety about lung cancer risk, clinicians made efforts to downplay this.
Conversely, some patients found that this caused process harms such as delays and
miscommunications.
Conclusion
Improved guidance and methods of risk differentiation for never-smokers are needed to avoid
diagnostic delays, over-reassurance, and clinical pessimism. This requires an improved
evidence base and initiatives to increase awareness among clinicians of the incidence of lung
cancer in never-smokers. As the proportion of never-smoker patients increases, this issue will
become more urgent.