Strahlentherapie und Onkologie : Organ der Deutschen Röntgengesellschaft ... [et al]
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Comparative Study
[The dosage-performance effects on Ca-Ski and HPK cells in relation to the dose and fractionation].
The steep decrease of dose and dose-rate in brachytherapy implies very different radiobiological considerations of the biological effectivity. ⋯ Changing a LDR- into an HDR-brachytherapy the equivalent factors close to the source have to be selected low and with increasing distances from the source high respectively higher-the major problem for a mathematical formula. The reduction of the dose in HDR-radiation therapy is a compromise in order to limit side effects caused by a radiation. The trade-off is a small therapeutic range and reduced therapeutic effectivity at the tumor. The percutaneous dose at the pelvis wall has to be reduced if at the same time an HDR-brachytherapy will be carried out-to avoid side effects.