[Quantification of the biological effect of photons and electrons. 2. Probability of tumor destruction]

The study comprises two subjects: the probability of destruction of the irradiated tumor and the tumor immunogenicity and its changes in the course of radiotherapy. The distribution of Poisson was adopted in order to describe the tumor destruction. The probability of tumor destruction is analysed under consideration of the "critical cell number". The other part of the study deals with the immune system and its radiosensitivity. It is demonstrated that the patient's immune reaction can contribute to the tumor destruction if the irradiation planning is made in an adequate manner. Furthermore, different irradiation techniques are compared to one another. Pendulum therapy, especially with large fields, seems to be no superior method despite its geometric advantages.