1988 Volume 4 Issue 2 Pages 119-129
Various type of 25 refractory tumors (16 : shallow-seated tumors, 9 : deep-seated tumors) were treated with radiotherapy and RF capacitive heating using HEH-500. Heating state, acute toxity and clinical result were analysed as follows.
Mean maximum intratumor temperature over 42°C and 41-42°C could be obtained in 9 (36%) and 8 (32%) respectively. Bulky shallow-seated tumors in the flat portion were capable of getting good heating state. But the temperatures of deep-seated tumors in the pelvis and lung could not be reached 42°C. In the rugged portions such as neck, supraclavicular region and chest wall after radical mastectomy, heatings tend to be unstable due to complaining of hot spot. The frequency of painful hot spot which was the cause of power limiting factor decreased from 81% to 41% by using large water bolus. Acute toxicity occured in 15 cases (12 : burns, 3 : subcutaneous indurations). There were no serious complications. Tumor response was evaluated by tumor shrinkage and complete responses were observed in 28% (7/ 25), partial responses in 40% (10/25) and no responses in 32% (8/25). Therefore the heating device (HEH -500) is thus suitable for heating of shallow-seated bulky tumors. It is considered that further improvement of applicators and boluses and increasing power of machine are necessary in order to heat deepseated tumors and other various site of tumors properly.
