The precise frequency of ALK in Latin American population has not been determined. Studies isolated in some Latin American countries like Brazil report a frequency of 3.2%, Argentina of 4.2% and Mexico of 9.0% of ALK fusion in a small number with lung cancer. Reliable information about ALK frequencies and disparities among ethnic groups is critical. Our study pretends to know the frequency and clinical characteristics of ALK rearrangement of Latin American patients with NSCLC. Discusses the difficulty of having a single diagnostic test for this chromosome abnormality.