Clinical efficacy and safety of adjuvant EGFR-TKIs for resected stage IB lung adenocarcinoma: A real-world study based on propensity score matching

Abstract

Abstract Background Adjuvant therapy for stage IB non-small cell lung cancer (NSCLC) remains debatable. In this real-world study, we evaluate the efficacy and safety of adjuvant epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) for resected stage IB lung adenocaicinoma. Methods This real-world study recruited 249 patients diagnosed as stage IB after surgical resection from January 2013 to September 2021. Sixty-six (26.5%) patients received adjuvant targeted therapy (TKIs group) and 183 (73.5%) patients were enrolled to clinical observation (CO) group. Propensity score matching was applied to minimize the effects of observed confounders between the two groups, and 59 pairs of patients were matched. The primary endpoint was disease-free survival (DFS). Results Among the adjuvant TKIs group, 38 (64.4%) patients chose to receive icotinib, 27.1% (16/59) of patients took gefitinib, and Osimertinib was 5 patients’(8.5%) option. Median follow-up time was 30.8 months (range: 7–107 months). Two (3.4%) patients in the TKIs group and 10 (16.9%) patients in the CO group had disease relapse. The 3-year DFS rates were 98.3% in the TKIs group and 83.0% in the CO group (HR: 0.10, 95%CI 0.01–0.78; P = 0.008). DFS differences could be found in the entire cohort (P = 0.005) and matched cohort (P = 0.024) between the two groups. The multivariate analysis showed that adjuvant EGFR-TKIs was an independent factor for DFS (HR, 0.211; 95%CI, 0.045–0.979; P = 0.047), together with poor cell differentiation (HR, 5.256; 95%CI, 1.648–16.769; P = 0.005) and spread through air spaces (HR, 5.612; 95%CI, 1.137–27.700; P = 0.034). No patients discontinued the EGFR-TKIs due to the low occurrence rate of treatment-related serious adverse events. Conclusion Adjuvant EGFR-TKIs could significantly improve DFS among patients with stage IB lung adenocarcinoma than clinical observation, with a safe and tolerable profile. Retrospectively registered study: The Chinese Clinical Trial Registry (www.chictr.org.cn) indentifier was ChiCTR2200060931.