"Internal" hyperthermia is a type of thermotherapy by which heat is sup plied to tumor tissue in situ. There are three different techniques for pro viding internal hyperthermia: (1) interstitial hyperthermia using implanted needle probes, (2) intracavitary hyperthermia using probes introduced into natural body cavities, and (3) perfusional hyperthermia by means of ex tracorporal blood heating. Compared with external hyperthermia, internal hyperthermia has been preferentially accepted by on...