Epidermal growth factor receptor mutation status and adjuvant chemotherapy in resected advanced non-small-cell lung cancer

Abstract

Introduction: This study was to assess the association of epidermal growth factor receptor (EGFR) mutation status and efficacy of adjuvant chemotherapy in patients with fully resected IIIA-N2 non-small-cell lung cancer (NSCLC).

Materials and methods: Tumor samples (n = 150) from patients with IIIA-N2 NSCLC who either had or had not received paclitaxel plus carboplatin or vinorelbine plus carboplatin doublet adjuvant chemotherapy were analyzed for EGFR mutations. The association of the presence of EGFR mutations and survival was assessed.

Results: Mutations were identified in 43 (28.7%) patients (n = 25 in the no chemotherapy [observation] arm and n = 18 in the chemotherapy arm). Patients with EGFR mutations had statistically significant improved disease-free survival (41 months [95% CI, 25.1-56.9 months] vs. 20 months [95% CI, 15.0-25.0 months]; 2P = .005) and overall survival (50 months [95% CI, 37.6-62.4 months] vs. 25 months [95% CI, 20.8-29.2 months]; 2P = .001), regardless of treatment. The patients with wild-type EGFR had greater overall survival with chemotherapy compared with no adjuvant therapy (hazard ratio [HR] 4.748 [95% CI, 2.844-7.928]; 2P < .001). In contrast, in patients with EGFR mutation in the observation group compared with the chemotherapy group had longer median disease-free survival (49 months [95% CI, 35.1-62.9 months] for the observation arm vs. 30 months [95% CI, 23.8-36.2 months] for the chemotherapy arm, 2P = .195) and overall survival (59 months [95% CI, 43.9-74.1 months] vs. 33 months [95% CI, 24.7-41.3 months]; 2P = .050).

Conclusions: In this exploratory study, the status of EGFR mutations was associated with different clinical outcomes in patients with resected IIIA-N2 NSCLC. Further studies are required to confirm that a patient's adjuvant treatment may be customized to their EGFR mutational status.