Eighty-four patients with unresectable various malignant tumors had received radiofrequency (RF) hyperthermia in combination with radiotherapy and /or chemotherapy. Hyperthermia was applied for 50 to 60 minutes once or twice weekly by using RF capacitive heat delivery systems operating at 8 or 13. 56 MHz. Of 84 tumors, 18 were superficial and 66 were deeply seated. These deeply seated tumors consisted of 21 primary tumors (TN group), 11 recurrent tumors (RC group), 24 primary or metastatic liver tumors (H group) and peritoneal disseminations (P group). The rate of CR (complete response) and PR (partial response) in total tumors was 31% whereas 7 tumors showed CR, 19 PR, 37 NC (no change), 11 PD (progressive disease) and 10 NE (not evaluable). Those regression rates in TN, RC, H, P groups and superficial group were 9.5, 18.2, 45.8, 0 and 61.1%, respectively. Subjective effects as pain relief, improvement of passage through the alimentary tract and so on emerged in 32. 1%. The regression rate was related not with histology of tumor but maximum intratumoral temperature. These results supported that RF hyperthermia with radiation and anticancer drugs was useful especially for liver and superficial tumors.
