Across Europe, we observe a diversity of guidelines for biomarker testing for advanced NSCLC varying from recommended testing of a few genes and proteins (EGFR, ALK, ROS1 and PD-L1 in England) to testing 11 genes (including NTRK1/2/3 and ROS1) in France and the Netherlands4. This evidence concerns the gene ROS1 and non-small cell lung carcinoma.