120P Efficacy of postoperative radiotherapy (PORT) in stage IIIA-N2 non-small cell lung cancer: Meta-analysis of randomized controlled studies

Abstract

Although adjuvant systemic therapy is the standard in patients with stage 3A-N2 non-small cell lung cancer (NSCLC) who underwent curative surgical resection, discussions about radiotherapy (RT) continue. This meta-analysis evaluated the efficacy of randomized controlled trials (RCTs) investigating the addition of RT (PORT) (sequential or concurrent) to adjuvant ChT in patients with operated stage 3A-N2 NSCLC. Pubmed, Embase, Cochrane Library, and Clinical Trials databases were scanned, and original research articles published until December 01, 2021, were included. Data on overall survival (OS), disease-free survival (DFS), local-regional recurrence-free survival (LRFS), and distant metastasis-free survival (DMSF) were extracted from the included studies and jointly analyzed. As a result of the database search, 5 RCTs involving a total of 1138 patients were included in the analysis (three phase 3, two phase 2). In the joint analysis of these 5 studies, it was seen that PORT did not contribute to OS (HR: 0.99, CI 95% 0.82-1.18, p = 0.87). In the analysis for DFS, it was observed that PORT provided a survival advantage (HR:0.84, CI 95% 0.72-0.97, p= 0.02). In the joint analysis of 4 RCTs (n:637) reporting LRFS and DMFS results, it was observed that PORT provided a significant survival advantage in terms of RLFS (HR:0.66, CI 95% 0.51-0.84, p= 0.001), but it did not contribute significantly to DMSF ( HR:0.84, CI 95% 0.70-1.02, p= 0.06). In this meta-analysis; In stage 3A-N2 NSCLC, it was observed that PORT prolonged DFS and LRFS, but did not contribute to OS and DMSF. Considering the possible cardiopulmonary toxicities of RT in this patient group, it would be more appropriate to make a patient-based decision.