Radiotherapy for patients with completely resected pathologic IIIA(N2) non-small-cell lung cancer: a retrospective analysis

Introduction: Adjuvant radiotherapy in non-small-cell lung cancer (NSCLC) remains controversial,Whether the mutation status of epidermal growth factor receptor (EGFR) will affect the recurrence and survival of patients with resected NSCLC is rarely reported. Our purpose is to study the effect of postoperative radiotherapy on patients with stage IIIA(N2) NSCLC with EGFR mutation. Methods: Total of of 115 patients diagnosed with stage IIIA(N2) resected NSCLC were analyzed retrospectively. Their EGFR mutations were detected by real-time quantitative PCR and DNA sequencing technology together. Results: At a median follow-up of 34.2 months for the postoperative adjuvant radiotherapy (PORT) group and 31.0 months for the non-PORT group, PORT group significantly improved progression free survival (PFS) and overall survival (OS). The median PFS and OS in the EGFR mutant group were not significantly longer than those in the EGFR wild type group. The number of chemotherapy cycles, postoperative radiotherapy and the number of metastatic lymph nodes were independent factors influencing long-term survival. Conclusion: Our retrospective analysis showed that PORT can improve survival of patients with stage IIIA(N2) NSCLC. EGFR-mutant group with stage IIIA(N2) NSCLC has a tendency of a higher survival than the wild-type EGFR group, but there was no significant difference for both groups. The EGFR mutation status was not associated with PFS or OS of stage IIIA(N2) NSCLC.