Efficacy and Toxicity of Chemoradiotherapy with Carboplatin and Irinotecan Followed by Consolidation Docetaxel for Unresectable Stage III Non-small Cell Lung Cancer

Introduction: In 2003, consolidation docetaxel was a promising concept for unresectable stage IIIA/B nonsmall cell lung cancer (NSCLC). To test the hypothesis that chemoradiotherapy with carboplatin and irinotecan followed by consolidation docetaxel would be feasible and clinically active, we conducted a phase II study. Methods: Thirty-two patients with unresectable stage IIIA/B NSCLC received irinotecan (30 mg/m(2)) and carboplatin dosed to a target area under the concentration curve of 2, each administered weekly for 7 weeks. Concurrent radiotherapy was administered more than 7 weeks to a total dose of 63 Gy in 35 fractions. Consolidation docetaxel (75 mg/m(2)) was administered every 3 weeks for 3 doses 4 weeks after chemoradiotherapy. The primary end point was objective response rate by RECIST. Results: Complete responses occurred in 4 patients and partial responses occurred in 14, for an objective response rate of 56.3% (95% confidence interval [CI], 37.7-73.6%). Median progression-free survival was 6.5 months (95% CI, 4.6-13.5); median duration of survival was 14.8 months (95% CI, 6.9-27.3). The most common hematologic toxicity was leukopenia, which were grade 3 or 4 in 16 patients (50%). Radiation pneumonitis (grade >= 2) occurred in 13 of 31 treated patients (42%). Conclusions: These findings suggested that concurrent chemoradiotherapy with carboplatin and irinotecan followed by consolidation docetaxel is clinically active based on median survival in patients with unresectable stage III NSCLC; however, the 42% incidence of clinical radiation pneumonitis was unexpected and warrants further investigation to determine the mechanism and preventive strategies.