Thoracic surgery improved overall survival in patients with stage IIIB–IV epidermal growth factor receptor-mutant lung adenocarcinoma who received and responded to tyrosine kinase inhibitor treatment

Purpose: No large-scale, prospective, randomized study has evaluated the effect of thoracic surgery on patients with unresectable stage IIIB–IV epidermal growth factor receptor (EGFR)-mutant lung adenocarcinoma who received and responded to EGFR tyrosine kinase inhibitor (TKI) treatment. Therefore, we designed a propensity-score-matched, nationwide, population-based, cohort study to investigate the effects of thoracic surgery on patients with EGFR-mutant lung adenocarcinoma. Patients and Methods: We included patients with unresectable stage IIIB–IV EGFR-mutant lung adenocarcinoma and categorized them into two groups according to their treatment modalities and compared their outcomes: the case group consisted of patients who underwent thoracic surgery for lung tumors after receiving and responding to EGFR-TKI treatment and the comparison group consisted of patients who received EGFR-TKI treatment alone until tumor progression. Patients in both groups were matched at a ratio of 1:4. Results: The matching process yielded a final cohort of 1395 patients (279 and 1,116 in the case and comparison groups, respectively) who were eligible for further analysis. According to multivariable Cox regression analyses, the adjusted hazard ratio (aHR; 95% confidence interval [CI]) for thoracic surgery for lung tumors after EGFR-TKI use and tumor response (group 2) compared with EGFR-TKI treatment alone (group 1) was 0.445 (0.351–0.564). Conclusions: Thoracic surgery prolonged overall survival in patients with unresectable stage IIIB–IV EGFR-mutant lung adenocarcinoma who received and responded to EGFR-TKI treatment.