Lung cancer may harbor driver mutations affecting the function of Epidermal growth factor receptor (EGFR), Anaplastic lymphoma kinase (ALK), ROS proto-oncogene 1 (ROS1), B-raf proto-oncogene (BRAF), RET proto-oncogene (RET), MET proto-oncogene (MET), and NTRK, which can influence the selection of targeted therapies and treatment outcomes. The gene discussed is RET; the disease is lung cancer.