ROBERTSON,EUGENE SPECIAL LECTURE HYPERTHERMIA FROM THE CLINIC TO THE LABORATORY - A HYPOTHESIS

Recently reported thermal isoeffective dose-response relationships in human tumours confirm the existence of an effect of hyperthermia in co mbination with radiotherapy. The prognostically important thermal dose s are based upon the lowest temperatures achieved within rumours, and these thermal doses are well below those used in most laboratory studi es that have provided the rationale for hyperthermia treatment. Direct thermal cytotoxicity and thermal radiosensitization are insignificant at these low thermal doses. Other explanations for the mechanism of h yperthermia effect appear warranted. We hypothesize that hyperthermia at low thermal doses causes reoxygenation and hence direct radiosensit ization in vivo