EML4 and non-small cell lung carcinoma: In many cases, such as the echinoderm microtubule-associated protein-like 4 (EML4)-ALK fusion found in NSCLC, there are multiple fusion variants with different molecular weights, frequencies in NSCLC, protein stabilities (t1/2), and ALK inhibitor sensitivities [50,70,98,99] (Table 2).