Vitamin D and Thyroid Cancer

Accumulating evidence demonstrated that the active form of vitamin D, 1,25(OH)2D3, has antiproliferative, anti-apopitotic and prodifferentiating effects in several tumour types in preclinical studies. Several studies reported the impact of vitamin D on cancer risk particularly in breast and colorectal cancer, however, its effect on thyroid cancer is less known. This review focuses on the relationship of vitamin D and thyroid cancer under the light of the literature. Thyroid cancer is the most common endocrine cancer and also vitamin D deficiency is a common condition throughout the world. Some clinical studies showed that vitamin D deficiency is higher in patients with thyroid cancer. Preclinical studies evidenced that vitamin D has an effect on differentiation, reduction in tumor burden, and prevention of metastatic growth in thyroid cancer used alone or in combination with anticancer drugs. However, further clinical studies are needed to understand its impact on prognosis of thyroid cancer.