Echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase-targeted therapy for advanced non-small cell lung cancer: molecular and clinical aspects.

The identification of oncogenic genomic alterations is expected to facilitate the development of new molecularly targeted therapies for cancer. EML4 (echinoderm microtubule-associated protein-like 4)-ALK (anaplastic lymphoma kinase) was recently identified as a transforming fusion gene in non-small cell lung cancer (NSCLC). A small-molecule tyrosine kinase inhibitor of ALK, crizotinib, shows pronounced clinical activity in the treatment of patients with NSCLC positive for EML4-ALK, and it has rapidly entered into daily clinical practice. This review focuses on the biology and clinical features of, as well as diagnostic testing for, EML4-ALK-positive NSCLC. Current data on the efficacy and toxicity of crizotinib are also examined, and future directions for the treatment of NSCLC positive for ALK rearrangement are addressed.