Phase II Study of Irinotecan Plus Cisplatin as First Line therapy in Extensive Small-Cell Lung Cancer

Background: Irinotecan (topoisomerase I inhibitor) is effective as a monotherapy against small-cell lung cancer(SCLC). Cisplatin is also an important drug against SCLC. A phase II study of irinotecan combined with cisplatin was carried out to evaluate the efficacy and toxicity of this combined regimen as a first line treatment in patients with extensive SCLC. Methods: Thirty-nine patients with previously untreated extensive SCLC were enrolled in this study. Irinotecan 60mg/m(2) was administered intravenously on days 1, 8 and 15, and in combination with cisplatin 60mg/m(2) on day 1 and every 28 days thereafter. Four cycles of chemotherapy were given to the patients. Results: The overall response rate was 77% with a complete response (CR) rate of 8%. The median survival time, 1-and 2-year survival rate were 14.8 months, 60.9% and 27.6%, respectively. The median progression free survival time, 6- and 12-month progression free survival rate were 8.4 months, 75% and 18.8%, respectively. The WHO grade 3 or more toxicity encountered were leukopenia (23%), diarrhea (26%). Two patients changed their chemotherapeutic regimen and one patient died from severe diarrhea. Conclusion: The combination of irinotecan and cisplatin is effective as a first line therapy in extensive SCLC is effective, but has severe or fatal diarrhea as toxicity.