Clinical Efficacy and Safety of Icotinib as Adjuvant Therapy for Resected Stage IA Lung Adenocarcinoma: A Real-world Study.

BACKGROUND: The clinical benefit of adjuvant therapy in patients with stage IA non-small cell lung cancer remains uncertain. This real-world study was conducted to assess the effectiveness and safety of icotinib as postoperative adjuvant therapy in patients with stage IA lung adenocarcinoma. PATIENTS AND METHODS: This real-world study enrolled 386 patients with pathologically confirmed stage IA lung adenocarcinoma who underwent curative-intent complete resection (lobectomy or sublobar resection) with lymph node dissection or sampling from June 2014 to July 2024. Among them, 128 patients (33.2%) received icotinib as postoperative adjuvant targeted therapy (TKI group), while 258 patients (66.8%) were managed with clinical observation (CO group). Propensity score matching (1:1) yielded 89 well-balanced pairs. The primary endpoint was disease-free survival (DFS). DFS and overall survival (OS) were estimated using the Kaplan-Meier method. RESULTS: The median follow-up for the overall cohort was 35.88 months (range 12.71-131.42). After PSM, 1 patient (1.1%) in the TKI group and 12 patients (13.5%) in the CO group experienced disease relapse. The 3-year DFS rate was 100.0% in the TKI group versus 86.8% in the CO group (hazard ratio [HR] 0.07; 95% confidence interval [CI] 0.01-0.50; P = .008). Multivariable Cox regression analysis further identified adjuvant EGFR-TKI therapy as an independent predictor of improved DFS (HR 0.08; 95% CI 0.01-0.50; P = .007). No patient discontinued EGFR-TKI therapy owing to treatment-related severe adverse events. CONCLUSION: Compared with clinical observation, adjuvant icotinib was associated with a significant improvement in DFS among patients with stage IA lung adenocarcinoma and exhibited a favorable safety and tolerability profile.