The prevalence of EML4-ALK variants in patients with non-small-cell lung cancer: a systematic review and meta-analysis

Abstract

To investigate the prevalence of EML4-ALK variants in non-small-cell lung cancer (NSCLC) patients. Materials & methods: Database of Pubmed, Embase, Medline and Cochrane Library were searched systematically to April 2018. Results: A total of 39 articles including 1903 NSCLC patients with ALK positive were recruited. The overall pooled prevalence for EML4-ALK variant 1 to 3 was 81.84% (95% CI: 76.68–86.99%), ranging from 86.64% tested by RT-PCR to 70.85% tested by other methods (p = 0.00). Subgroup analysis showed that the pooled prevalences of variant 1, 2 and 3 were 40.38% (95% CI: 34.83–45.93%), 6.59% (95% CI: 4.27–8.91%) and 26.54% (95% CI: 20.89–32.2%), respectively. Conclusion: This present study provides the exact prevalence of EML4-ALK rearrangement in different variants for NSCLC patients with ALK positive.