Plasma and tissue levels of some lanthanide elements in the human colorectal lesions

Lanthanide (Ln) levels in plasma and tissues from colorectal patients and healthy subjects were determined by radiochemical neutron activation analysis. Results, precision, accuracy and sensitivity are presented and discussed. Mean plasma levels of La, Ce, Nd, Eu and Yb were significantly higher (p <0.01) in adenoma and adenocarcinoma patients compared to control subjects. Increasing concentrations of plasmatic La, Eu and Yb as well as Ln levels in tissue from healthy subjects, adenomatous polyps, and adenocarcinoma (A DK) patients were observed. Measured tissue level s of Ln were constantly higher in ADK and adenomatous polyps than in the adjacent normal tissues. These findings may reflect impaired calcium metabolism possibly involved in the early process of carcinogenesis leading to the development of ADK