Phase II trial of S-1 as third-line or further chemotherapy in patients with advanced non-small-cell lung cancer

This study was conducted to evaluate the efficacy and safety of S-1 in patients with advanced non-small-cell lung cancer (NSCLC), receiving two or more prior chemotherapy regimens. S-1 was administered orally for 14 consecutive days, followed by a 7-day rest period. This treatment course was repeated until disease progression or intolerable toxicity occurred. From 2010 to 2012, 45 patients were enrolled in this study. Of the 45 patients, 4 patients [8.9 %, 95 % confidence interval (CI) 0.6-17.2 %] exhibited a partial response and 24 patients (53.3 %) exhibited stable disease. The disease control rate was 62.2 % (95 % CI 48.1-76.4 %). Median progression-free survival was 71 days, and median survival time was 205 days. Four patients had grade 3 hematological toxicities, but toxicities of grade 4 were not observed in this study. Although S-1 monotherapy as third-line treatment or beyond was well tolerated, the response rate for this regimen did not demonstrate sufficient activity for patients with advanced NSCLC.