While the ALK gene has been included in the drug label of crizotinib since 2011, testing of ROS1 rearrangements for treatment of patients with NSCLC has recently been added to the label of crizotinib by the FDA (March 2016) and by the EMA (September 2016) for first line therapy [4–6]. The gene discussed is ROS1; the disease is non-small cell lung carcinoma.