Radiofrequency-induced hyperthermia in the prostate.

A high frequency radiator has been developed for the treatment of prostate cancer by hyperthermia. The applicator produces a deep seated hot spot. The radiator has an outer diameter of 20 mm and an insertable length of about 175 mm. A high frequency cylindrical slot antenna inside the applicator is cooled by water. The frequency used is 433.9 MHz, one of the frequencies allowed for medical therapy in the F.R.G. A control system regulating the power output of the radiator avoids damage to the tissue around the prostate, especially the rectum mucosa and the tissue between rectum and prostate. About 60 experiments with male dogs proved that local heating of the prostate is possible with the help of the developed applicator without any damage in the surrounding tissue.