ABSTRACT
The treatment of superficial cancerous tumors with heat alone or in various combinations with ionizing radiations is not a new idea and dates back to the beginning of the century. The history of the use of microwave heating in cancer therapy is simpler because of the late development of high power generators which necessitate high technology. The most important ultrasound interaction with biological structures is heat dissipation, and to a lesser extent, cavitation effects creating “microstreaming”. The experimental and clinical data demonstrate that ultrasound fields perturb standard ternperature probes to a very small extent. The temperature of the water cooling system can be changed during the treatment to decrease the inverted skin thermal gradient. The efficiency of hyperthermia alone in the treatment of these superficial tumors is low, but there is scientific evidence in the literature and from our own clinical data that hyperthermia combined with radiation therapy has a synergistic effect on tumor response.
