Some patients with melanoma may have tyrosinase mRNA in their blood [129]; patients with breast cancer may have telomerase mRNAs [130]; patients with thyroid cancer may have CK19, mammaglobin, 5T4, and circulating thyroid-stimulating hormone receptor (TSHR) mRNAs [131]; patients with lung cancer may have 5T4 mRNA [132]; and patients with colorectal cancer may have CEA and CK19 mRNAs [133]. This evidence concerns the gene KRT19 and thyroid cancer.