Non-small cell lung cancer patients with EML4-ALK fusion gene are insensitive to cytotoxic chemotherapy

Abstract

Background: Although patients with the echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase gene (EML4-ALK) re-arrangement and epidermal growth factor gene EGFR mutations have proven sensitive to specific inhibitors, there is currently no consensus regarding the sensitivity of non-small cell lung cancer (NSCLC) patients with such mutations to cytotoxic chemotherapy.

Patients and methods: The responses to first-line cytotoxic chemotherapy were retrospectively compared between advanced or postoperative recurrent patients with non-squamous NSCLC who harbor the EML4-ALK fusion gene (ALK+), EGFR mutation (EGFR+), or neither abnormality (wild-type).

Results: Data for 22 ALK+, 30 EGFR+, and 60 wild-type patients were analyzed. The ALK+ group had a significantly lower response rate than the other two groups. Progression-free survival was significantly shorter in the ALK+ cohort compared to the EGFR+ (p<0.001) and wild-type cohorts (p=0.0121).

Conclusion: NSCLC patients with the EML4-ALK fusion gene might be relatively insensitivite to cytotoxic chemotherapy.

Keywords: Non-small cell lung cancer; anaplastic lymphoma kinase; cytotoxic chemosensitivity; epidermal growth factor mutation.