[Thermal radiosensitization in vitro and its implication to radiotherapy].

Thermal radiosensitization and the possible mechanism are reviewed. In vitro studies suggest that hyperthermia can enhance cell killing by radiation resulting in a steeper slope and smaller shoulder of the cell survival curve, compared to the survival were following radiation clone. Molecular studies suggest that inhibition of DNA synthesis and or repair of DNA damage by hyperthermia might be major causes of the thermal radiosensitization. When the curve is fitted by linar quadratic (L-Q) model, a increased number of beta, while relatively stable amount of alpha values are shown for survival curve to radiation combined with hyperthermia. This implies that when a larger radiation dose (greater than or equal to 4 Gy) is combined with hyperthermia, the enhancement would be greater in thermal radiotherapy.