Genes coding for proteins involved in the immune response (prostaglandin E2, microsomal prostaglandin E2, cyclooxygenase 2, and IL24) have been suggested to be induced by RET/PTC, indicating that the expression of the oncogenic fusion protein RET/PTC is critical not only in thyroid cancer pathogenesis but also in the elicitation of inflammatory response [130–132]. This evidence concerns the gene PTGS2 and thyroid cancer.