ALK and non-small cell lung carcinoma: A fusion protein between the N-terminal portion of the echinoderm microtubule-associated protein-like 4 (EML4) protein and the intracellular signaling portion of ALK[10] tyrosine kinase receptor, which has recently[11] been identified in a small subset of patients with NSCLC, is now recognized as an important oncogenic driver in NSCLC.