A multi-institutional phase II trial of consolidation S-1 after concurrent chemoradiotherapy with cisplatin and vinorelbine for locally advanced non-small cell lung cancer

Aim: To evaluate the efficacy and feasibility of the consolidation therapy of the oral fluoropyrimidine agent S-1 after concurrent chemoradiotherapy for unresectable stage III non-small cell lung cancer (NSCLC). Methods: Eligible patients had unresectable stage III NSCLC with performance status of 0 or 1. Chemoradiotherapy at a total dose of 60 Gy consisted of cisplatin (80 mg/m ²) on days 1 and 29, vinorelbine (20 mg/m ²) on days 1, 8, 29 and 36. Sequential consolidation S-1 therapy was commenced at a dose of 80-120 mg twice daily on day 57 with two cycles of 4 weeks administration and 2 weeks withdrawal. Results: Of the 66 patients, 65 were evaluated. Chemoradiotherapy was completed in 57 (87.7%) patients, and S-1 consolidation therapy was administered in 45 (69.2%) and completed in 31 (47.6%). Grade 3 pneumonitis developed in three patients with one dying of it. The response rate was 61.5% (95% confidence interval [CI], 48.6-73.3%). The median progression-free survival was 10.2 (95% CI, 8.6-13.7) months and median survival time 21.8 (95% CI, 15.6-27.6) months. The 1- and 3-year survival rates were 73.9% and 34.0%, respectively. Conclusions: Chemoradiotherapy with cisplatin and vinorelbine followed by S-1 consolidation demonstrated a reasonable overall survival in patients with stage III NSCLC. However, less than half of the patients completed this regimen, and the additional effect of S-1 was marginal compared with historical control. We concluded that chemoradiotherapy alone is still the recommended standard treatment for patients.