Besides, the National Comprehensive Cancer Network (NCCN) guidelines for NSCLC (2019, version 4) advocate testing of the tumor tissue to optimally identify mutations in EGFR, KRAS, HER2, ALK, ROS1, MET, BRAF, RET, and NTRK genes [100]. The gene discussed is ROS1; the disease is non-small cell lung carcinoma.