In addition, the exosomal long non-coding RNA growth arrest-specific transcript 5 (GAS5) was found to be downregulated in non-small cell lung cancer compared with healthy controls, and the combination of exosomal GAS5 with CEA yielded an AUC of 0.929, with more modest performance for stage I disease (AUC 0.822) (Li et al., 2019a). This evidence concerns the gene GAS5 and non-small cell lung carcinoma.