ALK and lung cancer: Crizotinib is a multitargeted tyrosine kinase inhibitor that inhibits anaplastic lymphoma kinase (ALK), ROS1, and mesenchymal‐epithelial transition (MET) receptors, and has demonstrated significant improvement in progression‐free survival (PFS) over chemotherapy as both first‐line and second‐line treatment of patients with ALK‐rearranged advanced nonsmall cell lung cancer (NSCLC) 1, 2.