AN ATOMIC BASIS OF CANCER — LANTHANIDE TRACE ELEMENT AS A TUMOR LOCALIZER

Abstract

An approach to define cancer is proposed and our work is reviewed. We have tried to localize (or mark) a malignant tumor from its benign environment by injecting a small amount of a lanthanide into a tumor-bearing nude mouse to see how a lanthanide can localize in a tumor. In order to see a contrast from its environment, we measured a trace element distribution in several organs or tissues of a nude mouse also. We have tried to enhance the effectiveness of a lanthanide with hematoporphyrin derivatives, and have extended our animal experiment to analyze an elemental distribution in human brain tumors. We have found the particle induced X-ray emission (PIXE) analysis a convenient and practical method for our purpose. A mathematical model for a human glioma growth is introduced and a dynamical model, a generalized predator prey model, is proposed. Some significant features of our findings in each topic are discussed in the respective section.