Abstract
Thyroid cancer is one of the leading causes of death worldwide. There have been several risks factors linked with thyroid cancer such as genetics, exposure to radiation, body weight and insulin resistance. Poorly differentiated and recurrent metastatic thyroid cancer cell carcinoma remains a therapeutic challenge because of its strong resistance to both chemotherapy and radiation therapy. Immunotherapy might play a role in the treatment of patients with metastatic thyroid cancer. In this paper, we discuss the potential causes of thyroid cancer, pathophysiology, and currently available molecular targeted therapy for refractory metastatic thyroid cancers and common side effects of treatment.