Efficacy study of metronomic chemotherapy in metastatic NSCLC.

Abstract

e19092 Background: Metastatic lung cancer patients are at best treated palliatively. We evaluated the effects of metronomic chemotherapy on survival outcomes in this population. Methods: Thirty four subjects with treatment refractory (n=26) and treatment naive (n=7) metastatic lung cancer were included in a open label single arm efficacy study of metronomic chemotherapy. Patients were given a chemotherapy regimen of Tab. Cyclophsophamide 50 mg once daily and cap. etoposide 50 mg once daily, 3 weeks on and one week off in 28 day cycle over a minimum period of 3 months or until the progression of their disease whichever was earlier. Patients were assessed for treatment response using RECIST criteria (version 1.1) and duration of progression free survival and overall survival. Data were analysed using Kaplan Meier survival analysis. Results: The mean age of the study population was 63.4 ±11.2 years. The mean duration of metronomic chemotherapy was 94.9 ±60.4 days. Overall 64.7% had progressive disease and 26.5% had stable disease. There was a significant improvement in overall survival in those with ECOG performance status of 1 compared to ECOG status of 2 (median survival =240 vs.52 days, Log Rank Mantel Cox =11.32, p=0.001) and pathology grade 2 compared to grade 3 (median survival =200 vs. 37 days, Breslows Wilcoxon =5.76, p=0.02) and stable disease on RECIST compared to progressive disease following metronomic chemotherapy (Median survival =360 vs. 50 days, Log Rank Mantel Cox =8.68, p=0.003). There was also a significant improvement in progression free survival in those with ECOG performance status of 1 compared to ECOG status of 2 (median survival =98 vs. 52 days, Log Rank Mantel Cox =6.62, p=0.001) and in grade 2 compared to grade 3 disease (mean survival =97 vs.32 days, Log Rank Mantel Cox =4.73, p=0.03). Tumor load and multiple organ sites of disease did not seem to influence survival. Conclusions: The results suggest stable response in about one third of study population, favorable progression free and overall survival rates following metronomic chemotherapy. Performance status is important predictors in this category of population.