Li et al. [42] showed that FLI1 exon circRNA is a novel oncogenic driver that promotes small cell lung cancer metastasis through the miR584/ROCK1 pathway, and proposed serum exosomal FECR1 as a promising biomarker that could be used to follow the disease progression of small-cell lung cancer. This evidence concerns the gene FLI1 and small cell lung carcinoma.