Micronutrient status (calcium, zinc, vitamins D and E) in patients with medullary thyroid carcinoma: A cross-sectional study.

OBJECTIVE: The aim of this study was to evaluate the micronutrient status of Iranian patients with medullary thyroid carcinoma (MTC) and to analyze potential relationships with respect to MTC risk.

METHODS: This was a cross-sectional study (Tehran Thyroid Cancer Survey 2015-2016). We measured and compared preoperative serum calcium, zinc, and vitamins D and E in patients with MTC and healthy controls. Forty cases with MTC and 40 (age-, sex-, and body mass index-matched) healthy controls voluntarily participated in the project.

RESULTS: Serum calcium, zinc, and vitamin D and E concentrations were lower in the patients with cancer (PCa < 0.001, PZn  = 0.01, PD  = 0.056, PE  = 0.002) than in the healthy controls. We found that serum calcium remarkably associated with enhanced risk for thyroid cancer (odds ratio [OR], 6.5; P = 0.001). Likewise, serum vitamin E was linked to the risk for cancer (OR, 1.31; P = 0.056). Moreover, serum zinc was correlated with vitamin E and calcium (r = +0.23; P = 0.04 and r = +0.25, P = 0.03; respectively). We also observed a correlation between calcium and vitamin E (r = +0.27; P = 0.02).

CONCLUSIONS: A multiple-micronutrient decrease was confirmed in patients with MTC. A low serum calcium level was a potent risk factor for MTC. Findings from the present study suggest that dietary intake and/or supplementation of micronutrients, especially calcium and vitamin E, may be beneficial in reducing the risk for thyroid cancer.