In 119 tumor lesions of ESCC, there were close to 40% of cases positive for both DKK1 and CKAP4, about 30% of cases positive for either CKAP4 or DKK1, and approximate 30% negative for both (Shinno et al., 2018). This evidence concerns the gene CKAP4 and esophageal squamous cell carcinoma.