Hyperthermia with radiotherapy

The use of hyperthermia together with radiotherapy in the treatment of relatively radioresistant tumours has been widely studied. In this preliminary non control study we used a 8MHz RF capacitive heating machine together with temperature probes inserted into the tumours under local anaesthesia. 27 patients with advanced post-radiation tumour recurrences as well as known radioresistant tumours were selected for treatment with hyperthermia and radiation. 7 patients withdrew from the study because of their intolerance to heat. 3 patients received superficial skin burns. Of the 20 patients studied, we were able to obtain moderate hyperthermia in most cases. 2 patients showed complete responses and 13 partial responses, giving rise to a total response rate of 75%. Some of the technical difficulties in achieving satisfactory hyperthermia are discussed. These include insertion of multiple probes into the body and the problem of achieving uniform heating of the tumour. Advances in hyperthermia can be expected with the development of improved methods of heat delivery and temperature measurements. However, presently methods of heat delivery can be improved by careful adjustment of the heating applicators and manipulation of cooling pads to avoid areas of excessive heating. Further clinical trials should be carried out to establish the optimum technique of hyperthermia.