A previous study by Stollberg et al. demonstrated that among 36,537 patients, CEA was used for 43.9% of all tumor marker tests in the clinic, and glycoproteins like CA125, CA15-3, and CA19-9 were used 17.7%, 15.8%, and 14.9% of the time, respectively [63]. This evidence concerns the gene CEACAM5 and neoplasm.