A comparison of schedules combining fractionated hyperthermia and irradiation in mice

A comparison was made of three study arms delivering localized fractionated hyperthermia followed by irradiation for two weeks. The treatment results demonstrated 18-week survival and NED survival to be 35 per cent (7/20) and 30 per cent (6/20) respectively for heat and irradiation 5 days per week, 57.9 per cent (11/19) and 52.6 per cent (10/19) for combined treatment 3 days per week and 27.8 per cent (5/18) for heat 3 days per week and irradiation 5 days per week. It is felt that thermotolerance will account for the lack of difference between 24 h and 48 h irradiation schedules when irradiation is given daily. Irradiation fraction size, however, is suggested as a moderating variable as well.