Hypermethylation of RASSF1 and SLC5A8 promoter regions was found to be higher in both tumor tissue samples and ctDNA of patients with PTC compared to those with benign thyroid nodules, and hypermethylation of the promoter regions of SLC5A8 in ctDNA was significantly associated with stage of PTC [43]. This evidence concerns the gene SLC5A8 and neoplasm.