Twenty Chemical Element Contents in Normal and Cancerous Thyroid

Thyroid cancer is an internationally important health problem. The aim of this exploratory study was to evaluate whether significant changes in the thyroid tissue levels of Ag, Br, Ca, Cl, Co, Cr, Cu, Fe, Hg, I, K, Mg, Mn, Na, Rb, Sb, Sc, Se, Sr, and Zn exist in the malignantly transformed thyroid. Thyroid tissue levels of twenty chemical elements were prospectively evaluated in 41 patients with thyroid malignant tumors and 105 healthy inhabitants. Measurements were performed using non-destructive energy-dispersive X-Ray fluorescent analysis combined with instrumental neutron activation analysis with high resolution spectrometry of short– and long-lived radionuclides. Tissue samples were divided into two portions. One was used for morphological study while the other was intended for chemical element analysis. It was found that contents of Ag, Br, Cl, Co, Cr, Cu, Hg, K, Mg, Na, and Rb were significantly higher (approximately 12.8, 9.3, 2.3, 1.4, 1.6, 3.4, 19.6, 1.6, 1.6, 1.3, and 1.5 times, respectively) while content of I lower (nearly 26 times) in cancerous tissues than in normal tissues. In our opinion, the increase in levels of Ag, Br, Cl, Co, Cr, Cu, Hg, K, Mg, Na, and Rb, as well as the decrease in levels of I in cancerous tissue might demonstrate an involvement of these elements in etiology and pathogenesis of malignant thyroid tumors. It was supposed that the changes in levels Ag, Br, Cl, Co, Cr, Cu, Hg, I, K, Mg, Na, and Rb in thyroid tissue can be used as tumor markers. Keywords: Thyroid malignant tumors; Intact thyroid; Chemical elements; Energy-dispersive X-Ray fluorescent analysis; Instrumental neutron activation analysi