FTC, which represents 2%-5% of thyroid cancers, is associated with mostly mutually exclusive RAS mutation and PAX8-peroxisome proliferator-activated receptor ɣ (PPARɣ) fusion oncogene; however, Hűrthle cell cancer is genetically different from FTC 2, 3. This evidence concerns the gene PAX8 and thyroid cancer, nonmedullary, 2.