ROS1 rearrangement (ROS1+) is an actionable driver mutation that occurs in 1% to 2% of patients with non‐small‐cell lung cancer (NSCLC).1, 2, 3, 4 Crizotinib, an oral ALK/MET/ROS1 inhibitor, has shown marked antitumor activities in ROS1+NSCLC. The gene discussed is ALK; the disease is non-small cell lung carcinoma.