ALK and adenocarcinoma: ALK‐rearrangements have been discovered recently as an important driver mutation in NSCLC, and especially in advanced‐stage NSCLC, ALK‐mutation status has a major impact on how patients are treated.60, 61, 62, 63, 64ALK rearrangement is found in 3%–7% of patients suffering from stage IIIB or stage IV NSCLC, according to previous data.65, 66, 67 Adenocarcinomas harbor ALK mutations more frequently than squamous cell carcinomas.