ROS1 and neoplasm: Compared with predominantly tissue‐based CTAs (n = 83/85; 97.6%), the F1L CDx assay showed moderate PPAs of 47.4% and 64.5% for detection of NTRK and ROS1 fusions, respectively, likely reflecting methodological differences (i.e. plasma vs. solid tissue and DNA‐ vs. RNA‐based CTAs, differences in diagnostic methodology between laboratories, tumour shedding variability among patients [28]).