Sequential treatment of tyrosine kinase inhibitor and platinum-based doublet chemotherapy on EGFR mutant non-small cell lung cancer: a meta-analysis of randomized controlled clinical trials.

There is debate surrounding which treatment is superior in overall survival (OS) rates in patients with epidermal growth factor receptor (EGFR) mutant non-small cell lung cancer (NSCLC); first-line tyrosine kinase inhibitor (TKI) followed by second-line platinum-based doublet chemotherapy (PCT), or the reverse sequence. Cross treatment of first- and second-line TKI and PCT makes it difficult to deduce which sequence (TKI-PCT or PCT-TKI) is better for OS. Using the keywords "lung cancer" and "EGFR" we identified clinical trials within the PubMed database which were published between January 2006 and November 2016. Basic characteristics and OS with hazard ratio and 95% confidence intervals were searched and analyzed. In total, 457 articles were reviewed and nine clinical trials with 1,876 patients were of sufficient quality for further analysis. Fixed effects models were performed to pool the data in this meta-analysis. All nine studies were open-labeled, multicenter, Phase III randomized controlled clinical trials. The pooled hazard ratio was 0.96 (95% confidence interval: 0.84-1.10) for OS between first-line TKI followed by second-line PCT compared to the reverse sequence. No statistically significant heterogeneity ( I 2 =0, P =0.553) nor publication bias (Egger's P =0.991) was observed among these studies. In conclusion, there was no OS benefit between first-line TKI followed by second-line PCT compared to the reverse sequence in EGFR mutant NSCLC patients. Chemotherapy was still useful and irreplaceable for the treatment of NSCLC, especially for those patients with EGFR unavailable for testing.