Recurrence and Risk Factors for Postoperative Recurrence in Patients with Completely Resected Stage IA2 and IA3 EGFR-Mutated Lung Adenocarcinoma

다국어 초록 (Multilingual Abstract)

Introduction: Data on recurrence risk in patients with stage IA EGFR-mutated non-small cell lung cancer （NSCLC） remain limited. We investigated long-term recurrence outcomes and risk factors in patients with completely resected stage IA2–IA3 EGFR-mutated NSCLC.
Methods: This multicenter retrospective cohort study included patients from 12 academic institutions in South Korea who underwent curative-intent resection for stage IA2–IA3 EGFR-mutated NSCLC between 2010 and 2017. Recurrence-free survival （RFS）, overall survival, and risk factors for recurrence were evaluated using Cox proportional hazards regression analyses.
Results: A total of 314 patients were included, with a median follow-up of 79.3 months. Disease recurrence occurred in 50 patients （15.9%）. The 5-year RFS（define at first use） rates were 90.1% for stage IA2 and 86.4% for stage IA3 disease, with no significant difference between the 2 stages （P = 0.129）. In the multivariable analysis, a consolidation-to-tumor ratio （CTR） ≥ 0.5 （hazard ratio [HR], 5.274; 95% confidence interval [CI], 1.608–17.292; P = 0.006） and poor histological differentiation （HR, 3.401; 95% CI, 1.328–8.709; P = 0.011） were independently associated with recurrence. Age ≥ 65 years was the only independent predictor of mortality （HR, 5.027; 95% CI, 2.354–10.734; P 〈 0.001）.
Conclusions: Patients with completely resected stage IA2–IA3 EGFR-mutated NSCLC had favorable long-term outcomes, although recurrence occurred in approximately one-sixth of patients. A CTR of ≥ 0.5 and poor histological differentiation were independently associated with recurrence. These factors may help identify patients who could benefit from consideration of adjuvant treatment.

목차 (Table of Contents)

• Introduction∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙1
• Methods∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙3
• Results∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙7
• Discussion∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙20
• Conclusion∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙24
• References∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙25