Irinotecan and cisplatin with concurrent split-course radiotherapy in locally advanced nonsmall-cell lung cancer: a multiinstitutional phase 2 study

BACKGROUND: The purpose was to determine the efficacy and toxicity of irinotecan and cisplatin with concurrent split-course thoracic radiotherapy (TRT) in locally advanced nonsmall-cell lung cancer. METHODS: Fifty patients fulfilling the following eligibility criteria were enrolled: chemotherapy-naive, good performance status (PS, 0-2), age <75, stage III, and adequate organ function. The patients received irinotecan 60 mg/m(2) intravenously on Days 1, 8, and 15, and cisplatin 80 mg/m(2) intravenously on Day 1 in the first group. The doses were reduced to 50 and 60 mg/m(2), respectively, in the second group. Two cycles of chemotherapy were repeated every 4 weeks. Split-course thoracic radiotherapy of 2 Gy/day commenced on Day 2 of each chemotherapy cycle, with 28 and 32 Gy administered in the first and second cycles, respectively. RESULTS: Fifty patients were eligible and 48 (16 in the first, 32 in the second group) patients were assessable for response, toxicity, and survival. The overall response was 83% (95% confidence interval CI], 70%-93%). Grade 4 leukopenia, neutropenia, grade 3 or 4 diarrhea, pneumonitis, esophagitis, and fatigue occurred in 21%, 48%, 19%, 10%, and 19%, respectively. The median time to progression was 8.2 months. The median overall survival time and the 2- and 5-year survival rates were 20.1 months, 47.1%, and 17.1%, respectively. In subgroup analysis, grade 4 neutropenia, grade 3 or 4 diarrhea, the overall response, and the median survival times of the first/second groups were 63%/41%, 19%/19%, 75%/88%, and 13.1/33.4 months, respectively. CONCLUSIONS: This combined modality of irinotecan and cisplatin with concurrent TRT is active and further investigations are warranted at the second group dose level.