[Origin of malignant tumors of the upper respiratory and digestive tracts and the ear (from a clinicians-point of view). 2. Pathogenesis of metastases (author's transl)].

Growth and development of metastases depends on 1. Tumor cells themselves, 2. Manipulations on the primary tumor, 3. Lymphatic vessels in the surrounding area of the primary tumor, 4. Blood composition. 5. Extent of tissue resistence through which tumor cells pass. 6. Certain circulatory conditions of the blood. Tumor cells are distinguished from normal cells often by reduced (Verbrauchskoagulopathie, tendency to bleed). An increase in bloodclotting supports the development of haematogenic metastases and the tumor growth. Malignant tumors of the kidney and the intestines may develop micrometastases of the lungs which, for years, as dormant cells, remain undiscovered. Then after 12--14 years metastases (further satelites) are seen e.g. in the ENT-field. In the spreading of tumor cells the flow parameters of lymph and blood play a very important role.