The prevalence of EGFR mutations in lung adenocarcinoma patients with COPD: a middle income country experience

<bold>Background:</bold> The presence of Epidermal Growth Factor Receptor (EGFR) mutations is associated with improved outcomes in lung cancer patients. The association between EGFR mutations and Chronic Obstructive Pulmonary Disease (COPD) is not well-established. <bold>Aim:</bold> To investigate the prevalence of EGFR mutations in lung adenocarcinoma patients with COPD in middle-income country of South-Eastern Europe. <bold>Methods:</bold> Retrospective cohort study of lung adenocarcinoma patients who underwent spirometry and EGFR testing at the Institute for Pulmonary Diseases of Vojvodina, Sremska Kamenica, Serbia between April 2019 and December 2023. COPD was diagnosed by spirometry as postbronchodilator FEV1/FVC ratio<0.7. <bold>Results:</bold> Among 1818 patients with EGFR analysis, there were 706 patients with spirometry. Of those 408/706 were males (57.8%), 390/706 (55.2%) current smokers, 234/706 (33.1%) former smokers and 82/706 (11.6%) never smokers with a mean age of 57.7±8.4 years. EGFR mutations were present in 63/706 (8.9%) and COPD was diagnosed in 445/706 (63.0%) of the patients. The prevalence of EGFR mutations was lower in COPD patients compared to non-COPD patients (6.3% vs.13.4%, p<0.001) and decreased accros COPD stages (stage I 12.08%, stage II 2,52%, stages III and IV 0%, p<0.001). After adjusting for age, sex and smoking status COPD was no longer associated with EGFR positivity (aOR 0.61,95% CI 0.35-1.07, p=0.08). <bold>Conclusion:</bold> COPD patients with lung adenocarcinoma in middle-income country of South-Eastern Europe have low prevalence of EGFR mutations, especially in severe COPD. This effect could be caused by differences in smoking and gender status between COPD and non-COPD patients.