Trace elements in human cancerous and healthy tissues from the same individual: A comparative study by TXRF and EDXRF

In this work we studied the elemental distribution of P, S, Cl, K, Ca, Cr, Mn, Fe, Ni, Cu, Zn, Ni, Se, Br, Rb, Sr, I and Pb in normal and cancerous tissues of the same individual along several contiguous thin sections (up to 10 μm thick) of each tissue. Samples of healthy and carcinoma tissues, of colon, breast and uterus on a total of 7 citizens from German population, were analysed directly by total-reflection X-ray fluorescence (TXRF). The tissues were also analysed by normal energy-dispersive X-ray fluorescence (EDXRF).An additional application was performed by studying, by the same processes, 10 carcinoma samples of 10 Portuguese citizens from: rectum, sigmoid, thyroid, kidney, larynx and lung, in order to find out a similar correlation pattern in the studied elements in carcinoma tissues.As major conclusion of this work a similar pattern for almost all the analysed tissues were obtained for all the studied samples: increased or constant levels of P, S, K, Ca, Fe and Cu, and decreased levels of Zn and Br were found in carcinoma tissues, when compared with the corresponding healthy ones. Some exceptions were found in some samples for a few numbers of elements.When comparing the results obtained for both techniques, the patterns were the same, however not always the results did coincide. This can be explained by considering that the analysed samples were not exactly the same and the differences can be explained by inhomogeneities.