[Biological and physical approach to the improvement of radiotherapy]

A double blind trial of misonidazole (MISO) was undertaken. A total of 147 patients were enrolled. They were randomly allocated into two groups receiving either MISO or placebo. They were irradiated with 2 Gy 5 times a week to a total dose of about 60 Gy. 0.5g/m2 of MISO was given orally 4 hours before each irradiation. The effect of the treatment was evaluated as a decrease in the volume of the tumors. No radiosensitizing effect of the drug was observed. Twenty-nine tumors considered to be radioresistant were treated by RF hyperthermia combined with radiation. 48% of the tumors developed complete regression. No definite relationship between heat sensitivity of the tumors and their histological types was observed.