Effects of hyperthermia on radiosensitivity of normal and leukaemic lymphocytes

We measured the effects of X-irradiation plus incubation at elevated temperatures on peripheral blood lymphocytes from normal persons and from patients with chronic lymphocytic leukaemia. Counts of viable lymphocytes were based on morphological characteristics by phase microscopy. Dose-effect curves for X-irradiation were biphasic. The D0S for lymphocytes incubated at 39 and 41 degrees were significantly less than the D0 for 37 degrees. For both normal and leukaemia lymphocytes, X-irradiation was synergistic with hyperthermia at 39 degrees and 41 degrees.