[Selective local hyperthermy of tumor tissue. Homogenized energy supply also to deep-seated tissues by...

Based on results of selective tumor tissue hyperacidification and whole-body hyperthermy the paper deals with the advantages of local hyperthermy and gives a review of the various methods of energy supply for hyperthermy in living tissue. It follows a presentation of physical and biophysical fundamentals on selective local hyperthermy of tumor tissue by radiation, by r. f. rotational magnetic fields and by r. f. capacitor fields. Using a gelatine phantom for measuring the energy supply with the various modes of local hyperthermy it is then shown that it is solely the divergent rotational magnetic field which allows to substantially reduce the inhomogeneity of energy supply also in z-direction (increasing depth in body tissue) by introducing a relative raster motion of the applicator in x-y-direction (plane parallel to body surface). It is only the introduction of the x-y raster principle combined with a described dual system array (CMT Selectotherm System) which permits the high and rather homogeneous supply of thermal energy also to deep-seated tumor tissue in the patient without concomitant critical superheating of tissues near the skin. Finally the paper gives a theoretical derivation of the temperature profile for selective local hyperthermy of tumor tissue. With due consideration of heat dissipation by convection and conduction, this endeavour shows rather promising aspects for the therapeutic efficiency obtainable in each case of treatment.