Post-operative radiotherapy in N2 non-small cell lung cancer: A retrospective analysis of 175 patients

Background and purpose: Post-operative radiotherapy (PORT) in radically resected non-small cell lung cancer (NSCLC) has the aim to reduce loco regional recurrence and to improve overall survival. PORT has been evaluated in several trials but indication to post-operative treatment in N2 patients is still debated. Material and methods: We retrospectively analyzed 175 patients treated at University of Florence between 1988 and 2004 with completely resected NSCLC stages IIIA-IIIB, N2 disease. Surgery consisted in a lobectomy in 58.9% and in a bi-lobectomy or in a pneumonectomy in 41.1% of patients. One hundred and nineteen patients underwent PORT and 56 patients did not receive PORT (no-PORT). Results: At a median follow-up of 27.6 months (range 4-233 months), we found a significant reduction in local recurrence (LR) in PORT group (log-rank test p = 0.015; HR: 0.45; 95%CI: 0.24-0.87). No statistical difference were found in terms of overall survival (OS) (log-rank test p = 0.92). Concerning other prognostic factors, male sex emerged as statistically significant (HR:4.33;1.04-18.02) on local progression free survival (LPFS) at univariate analysis. Acute and long-term toxicity was mild. Conclusion: Our retrospective analysis showed that PORT may improve local disease control in N2 NSCLC patients with an acceptable treatment-related toxicity.