Advanced Brachytherapy Physics - Vienna 2016

Example: influence of the number of BT Fx

Random uncertainties and dose response for different fractionation schemes

For target: using 1 Fx vs 2-5Fx results in ~0 5% lower tumour control probability than . predicted by model

Example: random uncertainty  D 2cm³ = ± 20%/fx: • nFx=5 => observed morbidity @75Gy 8 5% . • nFx=4 => observed morbidity @75Gy 8.9% • nFx=3 => observed morbidity @75Gy 9.4% • nFx=2 => observed morbidity @75Gy 10.3% • nFx=1 => observed morbidity @75Gy 12.3%

“Can reduction of uncertainties in cervix cancer brachytherapy potentially improve clinical outcome?” Nesvacil et al. 2016, submitted to R&O