Hyperthermia in Cancer Therapy: Technical and Clinical Aspects

The possibility of significant antitumor activity associated with temperatures over 40° C was first documented by Busch in 1866. Since that time, several investigators have shown that heat alone can cause regression and cure of malignant tumors and that the effect of hyperthermia is related to both duration and level of heat. In recent years a rebirth of interest in hyperthermia was generated by results gained in several medical specialities by combining heat with irradiation and/or chemotherapy. Discussed are techniques for producing hyperthermia with electromagnetic fields. Using these techniques a broad spectrum of malignant tumors can be treated including skin tumors, tumors of the pelvis and thorax, and tumors as small as malignant intraocular neoplasms. Advances in hyperthermic tumor treatment are expected in future generations of ultrasonic and electromagnetic technology, such as improved means for high accuracy of tumor localization and heat delivery. Further work to evaluate thermal toxicity and thermotolerance, as well as sequencing and fractionation of hyperthermic and radiation doses, is indicated to maximize the potential for combined use of these treatment modalities in cancer therapy.