Genetic and epigenetic alterations in thyroid tumors include mutations (BRAFV600E, Ras, PI3K, PTEN, p53, b-catenin, anaplastic lymphoma kinase), translocation (RET-PTC) and paired box 8 (PAX8)-peroxisome proliferator-activated receptor-g (PPARG) as well as aberrant gene methylation (retinoic acid receptor beta, and tissue inhibitor of metalloprotease 3) [20]. This evidence concerns the gene PTEN and thyroid tumor.