A randomized phase III trial of irinotecan plus carboplatin versus etoposide plus carboplatin in patients with small cell lung cancer, extensive disease (SCLC-ED): IRIS-Study

Abstract

7523 Background: A Japanese randomized trial has shown superior survival for SCLC-ED patients receiving irinotecan+cisplatin as compared to etoposide+cisplatin. Our trial was performed to evaluate the effect of irinotecan+carboplatin compared to oral etoposide+carboplatin. Patients and Methods: In a phase III trial, patients with SCLC-ED were randomly assigned to receive carboplatin, AUC=4 (Chatelut formula) and irinotecan, 175 mg/m2, both on day 1 (IC) or carboplatin (Chatelut AUC=4) on day 1 and etoposide 120 mg/m2/day, orally, on days 1–5 (EC). In both arms, courses were repeated on day 21 with 4 cycles planned. Primary endpoint was overall survival (OS), secondary endpoints were quality of life, evaluated by EORTC-QLQ-C30 and QLQ-LC 13, and complete response rate. There were neither upper limits for age or performance status. Results: Between November, 2001 and July, 2005, 220 patients were randomized. 210 patients were eligible for analysis (other type of cancer, 8 pts., limited disease, 1 pt., elevated liver function tests, 1 pt.). Performance status (PS) 0: 20 patients, PS 1: 91, PS 2: 62, PS 3: 29, PS 4: 8. Median age IC was 67 years (46–81), EC 67 years (39–82). OS was 255 days (IC) versus 214 days (EC) (P=0.04, log rank test). HR for overall survival was 1.34, 95% CI: 1.01–1.79. 1-year survival was 35% vs 28%. CR was observed in 18 patients in the IC arm and 7 patients in the EC arm (P=0.02, chi-square test). There were no statistically significant differences with respect to haematological grade III-IV toxicity. No severe diarrhea was observed in the IC group. There were no significant differences regarding quality of life. Conclusion: Irinotecan + carboplatin is superior to oral etoposide + carboplatin with respect to overall survival in SCLC-ED. No significant financial relationships to disclose.