ALK and lung cancer: Non-small cell lung cancer (NSCLC) represents about 85% of all lung cancer diagnosis and, in the last ten years, an increasing number of activating oncogene mutations have been discovered in this setting: the most frequent ones are KRAS (20–30%), EGFR (10–15% of Caucasian patients and up to 40% of Asian patients) and ALK (anaplastic lymphoma kinase) gene.