Physics Bucharest 2017

The Uncertainty of RBE (by Oliver Jakel - HIT)

Relative Uncertainty in the SOBP: Variation of the RBE as a function of various parameters (depth, dose, beam energy, fractionation, tumor type, etc.) Precision probably around 10% Absolute uncertainty: Absolute value of the RBE, which determines the applied biological effective dose Accuracy of RBE(C12) probably around 20% - 30% Comparison: Clinical Proton-RBE: ~10-20% RBE for Brachytherapy ( 125 I and 103 Pd): ~1.5 (+-20%) Changes of fractionation schemes (using a/b ): ~15% “Correct doses” have to be evaluated in clinical studies