Clinical Outcomes and Safety of Concurrent Chemoradiotherapy in EGFR-Mutant Unresectable Stage III NSCLC

Abstract

Introduction

Concurrent chemoradiotherapy (cCRT) is the standard of care for unresectable stage III NSCLC, but whether EGFR mutation is a prognostic factor remains unclear. This study evaluated the efficacy and safety of cCRT in unresectable stage III EGFR-mutant NSCLC. This study aimed to describe and compare the efficacy and safety outcomes of patients with unresectable stage III NSCLC treated with cCRT in those with and without EGFR mutation.

Methods

Data from three randomized phase II trials in the Japan Lung Cancer Society database (n = 274; 116 EGFR mutant, 158 EGFR wild type) were analyzed. Outcomes were progression-free survival (PFS), overall survival, and safety.

Results

Patients with EGFR-mutant NSCLC exhibited significantly shorter PFS than patients with EGFR wild-type NSCLC (hazard ratio [HR] = 1.38; 95% confidence interval [CI]: 1.05–1.82; p = 0.021). The results were generally consistent without statistical deviation, regardless of subgroup characteristics. EGFR mutation was retained as a covariate in the final multivariate model for PFS (HR = 1.358; 95% CI: 0.977–1.886; p = 0.068). Overall survival was not significantly different between the groups (HR = 0.98; 95% CI: 0.70–1.38; p = 0.903). A higher incidence of grades 3 to 4 pneumonitis was observed in patients with EGFR-mutant NSCLC compared with patients with EGFR wild-type NSCLC (7.8% versus 2.6%).

Conclusion

Patients with EGFR-mutant unresectable stage III NSCLC exhibited significantly shorter PFS than patients with EGFR wild-type NSCLC. The median PFS was generally consistent with that of the control arm in the LAURA trial. Increased pneumonitis risk necessitates close monitoring in patients with EGFR-mutant unresectable stage III NSCLC.