These 55 articles evaluated a total of 135 genes, including eight genes (RASSF1, TSHR, PTEN, electro genic sodium and chloride-dependent sodium-coupled solute transporter [SLC/NIS], DAPK, P16, RARβ2, and cadherin 1 [CDH1/E-cadherin] that have been shown to be associated with thyroid cancer in more than four studies; accordingly, we selected these eight TSGs for the meta-analysis. Here, CCL21 is linked to thyroid cancer.