The current study assessed the performance of the fully automated RT-PCR-based IdyllaTM GeneFusion Assay, which simultaneously covers the advanced non-small cell lung carcinoma (aNSCLC) actionable ALK, ROS1, RET, and MET exon 14 rearrangements, in a routine clinical setting involving 12 European clinical centers. This evidence concerns the gene ROS1 and non-small cell lung carcinoma.