Does adjuvant chemotherapy improve survival in non small cell lung cancer (NSCLC)? A pooled-analysis of 6494 patients in 12 studies, examining survival and magnitude of benefit

Abstract

7140 Background. Multiple randomized trials investigating the benefit of adjuvant chemotherapy in the post-operative setting in NSCLC have yielded conflicting results. With over 6000 patients included, we analyzed results of 12 reports over the past 10 years, in which patients received either platinum-containing chemotherapy (11 with cisplatin) or no chemotherapy. Methods. All phase III randomized trials and meta-analyses published as peer-reviewed papers or as abstracts from 1994 to 2004 were eligible. A pooled analysis was performed; event-based relative risk ratios (RR) with 95% confidence interval (CI) were derived. Primary end-points were overall survival (OS) and disease-free survival (DFS). Several sub-populations were also examined as in the table. Combined effect estimation was computed with both fixed- and random-effect model. An heterogeneity test was applied. Results. Eleven trials plus a meta-analysis (6494 patients) were gathered. When data were pooled and plotted, significant differences in favor of chemotherapy were seen in OS and DFS in the entire study population and in sub-populations; relative benefits of 6–13% and 10–11%, respectively. DFS benefits were greater than OS in all analyses. No significant heterogeneity was observed. Conclusions. Survival benefits with adjuvant chemotherapy are significant when: 1) all patients and studies are analyzed, and 2) when each sub-population (by stage, trial size, or publication/presentation type) is considered, given the limitations of pooled analysis. 3) The magnitude of benefit (RR 0.93) with this large population, and in sub-populations, appears to be smaller than generally perceived, raising issues of importance when considering the risks and benefits of treatment. No significant financial relationships to disclose.