Document Type : Research Articles
Department of Endocrinology and Metabolism, Zahedan University of Medical Sciences, Zahedan, Iran.
Department of Hematology and Oncology, Zahedan University of Medical Sciences, Zahedan, Iran.
Department of Pathology, Zahedan University of Medical Sciences, Zahedan, Iran.
Department of Endocrinology, AJA University of Medical Sciences, Tehran, Iran.
Department of Pediatric Nephrology, Zahedan University of Medical Sciences, Zahedan, Iran
Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
Objective: In recent decades, the incidence of thyroid cancer has increased throughout the world. It is unclear whether factors such as vitamin D deficiency may have been involved in this increase. The present case-control study was conducted to examine any association between Vitamin D deficiency and thyroid cancers. Methods: The study was conducted on 85 patients with differentiated thyroid cancer diagnosed based on fine needle aspiration biopsy as the case group and 85 healthy controls. Serum levels of vitamin D were evaluated before thyroidectomy. For each patient in the case group, one healthy euthyroid person without any thyroid nodules from the general population matched based on season, sex, age (± 1 year) and BMI (± 1) was selected. Finally, 85 pairs were obtained considering inclusion and exclusion criteria. Thyroid function, thyroid antibodies and serum vitamin D were assessed and thyroid sonography was performed in all participants. Results: In the patient group, 72 (85%) were female and 13 (15%) were male. The mean (SD) serum vitamin D level was 8.00 (±3.7) in patient group, as compared to 13.4 (±7.90) in the control group, the difference being significant (OR: 6, 95 % CI: 1.02-113.3; P=0.046). Conclusion: A significant association was noted between vitamin D deficiency and differentiated thyroid cancer. Further studies with a prospective design are necessary to further define the roles of this factor.