[Radiotherapy on the basis of quality of life]

Considering the relationship between tumor lethal dose and normal tissue tolerance: the therapeutic ratio, radiation oncologists have been performed the radiotherapy for cancer patient. The basic principle of radiotherapy is to have a good result (curability), to be tolerable in side effects and to have a comfortable life after radiation. Radiotherapy is the important strategy for an early stage of cancer with conserving the function and structure, and for an advanced or a recurrent stage of cancer with contributing to improve the quality of life. Recently, advantage of radiation tools and supportive care of cancer treatment, have been able to decrease the incidence of late injuries and complications. Radiotherapy must be planned on basis of considering therapeutic ratio and should be performed with optimum radiation in the multimodal treatment for cancer.