PURPOSE: Although positive epidemiologic associations between COPD and lung cancer have been well established, similar data correlating asthma with lung cancer have shown conflicting results in the literature.
METHODS: Subjects with lung cancer and their age- and sex-matched non-cancer controls were enrolled into this study. A total of 874 charts were collected from an 11 year period between 1998 and 2009. Lung cancer cases were obtained from the University of Missouri Cancer Registry and controls were obtained from the University's electronic medical record system. Lung cancer diagnosis and histology were confirmed prior to enrollment. We analyzed 759 of the 874 total charts screened, excluding COPD diagnosis which is a known independent risk factor for lung cancer.
RESULTS: Of the 759 subjects that were enrolled in the study, the prevalence of lung cancer was 46.2% among asthmatics (n=13), compared with only 22.5% among non-asthmatics (n=746). This difference was significant (one sided p-value=0.05, odds ratio (OR)=2.9). Age-adjusted OR of 5.7 also showed a positive correlation between asthma and lung cancer (p=0.005).
CONCLUSION: Data from The Cancer Registry in Central Missouri suggests a strong epidemiologic correlation between asthma diagnosis and lung cancer development. Chronic repeated inflammatory insults to the airways from asthma may be adequate to initiate carcinogenesis, although the mechanism(s) remain to be elucidated.
CLINICAL IMPLICATIONS: Correlating repeated inflammatory insults from asthma as a potential risk for lung cancer development underscores the importance of more aggressive management of inflammatory airway disease, development of diagnostics for early and ideally non-invasive screening and risk stratification, and promotion of additional research on the mechanisms of carcinogenesis induced by inflammation.
DISCLOSURE: Vamsi Guntur, No Financial Disclosure Information; No Product/Research Disclosure Information