Distinguish Thyroid Malignant From Benign Alterations Using X-Ray Fluorescence And Neutron Activation Analysis Of Chemical Element Contents In Nodular Tissue

Author(s): Vladimir Zaichick*

Background: Thyroid Benign (TBN) and Malignant (TMN) Nodules is a common thyroid lesion. The differentiation of TMN often remains a clinical challenge and further improvements of TMN diagnostic accuracy are warranted.

Objective: The aim of present study was to evaluate possibilities of using differences in Chemical Elements (ChEs) contents in nodular tissue for diagnosis of thyroid malignancy.

Methods: Contents of nineteen ChEs including silver (Ag), calcium (Ca), chlorine (Cl), cobalt (Co), chromium (Cr), cooper (Cu), iron (Fe), mercury (Hg), iodine (I), potassium (K), magnesium (Mg), manganese (Mn), sodium (Na), rubidium (Rb), ammonium (Sb), scandium (Sc), selenium (Se), strontium (Sr), and zinc (Zn) were prospectively evaluated in nodular tissue of thyroids with TBN (79 patients) and to TMN (41 patients). Measurements were performed using a combination of non-destructive nuclear analytical methods: X-ray fluorescence and instrumental neutron activation analysis.

Results: It was observed that in TMN tissue means of Br, Fe, I, Se, and Zn mass fractions are approximately 3.0, 1.6, 14, 1.4, and 1.3 times, respectively, lower, while the means of Ca, K, Mg, and Rb mass fraction are 94%, 56%, 36%, and 62%, respectively, higher those in TBN tissue. Mean contents of Ag, Cl, Co, Cr, Cu, Hg, Mn, Na, Sb, Sc, and Sr found in the TBN and TMN groups of nodular tissue samples were similar.

Conclusion: It was proposed to use the I mass fraction as well as I/Ca, I/K, I/Mg, and I/Rb mass fraction ratios in a needle-biopsy of thyroid nodules as a potential tool to diagnose thyroid malignancy. Further studies on larger number of samples are required to confirm our findings and proposals.