Docetaxel and carboplatin is an active regimen in advanced non-small-cell lung cancer: a phase II study in Caucasian and Asian patients

Background: The purpose of this study was to report response rates, survival and toxicity in advanced non-small-cell lung cancer (NSCLC) following docetaxel and carboplatin, and to explore potential differences in these end points between Caucasian and Asian patients. Patients and methods: Sixty-eight patients of good performance status with Stage IIIB or IV NSCLC were entered on a phase II study at three sites in Australia and Singapore. Docetaxel 75 mg/m(2) and carboplatin AUC 6 were given every 3 weeks. Response to treatment and toxicity were graded by standard criteria. The Kaplan-Meier method was used to estimate survival rates, and subgroups compared by the log-rank test. Cox's proportional hazards regression was used to determine which potentially explanatory variables independently affected the outcome. Results: The response rate was 39% (95% confidence interval 27% to 52%), and 42% in evaluable patients. Response occurred in 65% of Asian and 31% of Caucasian patients (P = 0.01). Ethnicity was the only significant predictor of response in multivariate analysis. The 1-year survival rate was 53%. Performance status (P=0.021), ethnicity (P =0.035) and presence of bone or liver metastases (P=0.011) were independent predictors of overall survival. Neutropenia (grade IV in 73% of patients), febrile neutropenia (26% patients) and diarrhea (grade III/IV in 11% of patients) were the major treatment related toxicities. A high rate (three of six) of febrile neutropenia in Singapore, including one treatment-related death in the initial patients treated, resulted in a reduction in the carboplatin dose to AUC 4.5 at that site. Conclusions: This regimen is active in advanced NSCLC. The potential impact of ethnicity on efficacy and toxicity of treatment requires further investigation.