ROS1 and non-small cell lung carcinoma: Tests proposed for earlier stages of NSCLC include all targetable genetic alterations with therapies approved for use in the advanced setting (i.e., EGFR, ALK, ROS1, BRAF, NTRK1/2/3, MET exon 14 skipping, and RET) as well as PD-L1, HER2, and KRAS [39].