According to the authors' concept, different forms of trace element deficiency show some general rules of development. All of them are followed by a decrease of immune resistance. Trace element deficiency is never isolated, it is always characterized by trace element unbalance and is followed by a considerable disturbance of metabolism (mineral, lipid, carbohydrate and protein) with relevant manifestations. Reduced immune resistance and pluriglandular endocrinopathy create the conditions for various malignancies.