The biology and treatment of EML4-ALK non-small cell lung cancer

The fusion between echinoderm microtubule-associated protein-like 4 (EML4) and anaplastic lymphoma kinase (ALK) has recently been identified in a subset of non-small cell lung cancers (NSCLCs). EML4-ALK is most often detected in never smokers with lung cancer and has unique pathologic features. EML4-ALK is oncogenic both in vitro and in vivo and ALK kinase inhibitors are quite effective in pre-clinical model systems. More recently ALK inhibitors have entered clinical development and remarkably clinical efficacy has been observed in NSCLC patients harbouring EML4-ALK translocations. This review will focus on the biology, clinical characteristics, diagnosis and treatment of EML4-ALK NSCLC.