[The influence of high-frequency hyperthermia on Ehrlich-ascites carcinoma in the mouse]

On 988 NMRI-mice the influence of a single high-frequency hyperthermia of differing intensity in the decimeter-wave field was investigated regarding the course of the Ehrlich's-ascites carcinoma. The application of high frequency (461,04 MHz) was made with an electrode on an induction field of 3,8 cm diameter, and covers the whole peritoneal cavity. No significant prolongation of the survival time was achieved, neither by increasing the intensity up to the final rectal temperature of 40 degrees-43 degrees C, nor by selecting different therapeutic periods during the growth of the tumor (1, 3, 6, and 10 days after inoculation). In contrast to local tumors which can be cured solely by high frequency treatment in the chosen model of a generalized tumor (in which the tumor tissue cannot be separated), no significant therapeutic effect can be reached by sole thermotherapy--not even with the risk of extremous therapy-induced complication rates. An interesting field for research seems to exist as to what extent tumor proliferation kinetics can be influenced by high frequency.