Abstract
BACKGROUND: Chronic airway inflammation in asthma and/or chronic obstructive pulmonary disease (COPD) is presumed to be protumorigenic. The tumor inhibitory effect of inhaled corticosteroids (ICSs) used to reduce airway inflammation in patients with asthma and COPD remains unclear. OBJECTIVES: This study aimed to evaluate the impact of coexisting asthma and/or COPD on the survival of patients with lung adenocarcinoma. The effects of ICS treatment were also assessed. DESIGN: This retrospective, real-world cohort study was conducted at a cancer center. METHODS: The overall survival of a cohort of 1524 consecutive patients with lung adenocarcinoma who were enrolled between January 2011 and December 2019 and followed up until December 2022 was analyzed, followed by subgroup comparisons. RESULTS: A total of 283 patients had coexisting asthma and/or COPD. Among them, 212 had used ICSs. ICS users were predominantly women, older, and had more advanced-stage disease; moreover, there were fewer tobacco smokers, fewer comorbidities, and relatively severe obstructive impairments than non-ICS users. When restricted to stage 0-II diseases, patients with coexisting asthma and/or COPD had a lower 5-year overall survival rate (77% vs 90%, p < 0.001), with a hazard ratio of 1.8, in contrast to no difference among patients with stage III-IV disease. ICS users had a lower 5-year overall survival rate in both subgroups, although the difference was not statistically significant. CONCLUSION: The impact of cancer on prognosis may overwhelm the effects of asthma and/or COPD in patients with advanced-stage lung adenocarcinoma. The evaluation of the effects of ICS treatment appears to be confounded by intent and compliance, which can introduce bias in the opposite direction. However, investigating the treatment effects on asthma and/or COPD control would be beneficial. A systematic prospective study is required to define the role of the ICS.