ROS1 and non-small cell lung carcinoma: The approval of crizotinib in the US, an anaplastic lymphoma kinase (ALK)/ROS1/MET multi-targeted tyrosine kinase inhibitor (TKI), merely 4 years after the discovery of rearrangement in ALK in non-small cell lung cancer (NSCLC) represented a landmark in oncology drug development and a significant step toward the goal of personalized medicine in oncology (1).