RBE predictions by the BIANCA model for $in$ $vitro$ and $in$ $vivo$ irradiations in hadron therapy scenarios

BIANCA is a two-parameter biophysical model that simulates chromosome aberrations and cell death induced by ionizing radiation, including ions of interest for hadron therapy. In this framework, the model parameters were tuned to produce a radiobiological database describing the survival of V79 cells, chosen as a reference, after irradiation with different monochromatic ion beams. Afterwards, an approach was developed to produce analogous databases for other cell lines, starting from their photon response; this approach allows performing full predictions for, in principle, any cell line. These databases can be read by a radiation transport code or a treatment planning system (TPS). Recently, BIANCA was interfaced to the FLUKA Monte Carlo code, and was applied to predict cell survival and RBE in typical hadron therapy scenarios. Very good agreement was found with in vitro data on the survival of CHO cells exposed along Spread Out Bragg Peaks of protons, C- and He-ions. Furthermore, good agreement was obtained with in vivo RBE data on late effects in the rat spinal cord following irradiation with C-ions or protons. Finally, BIANCA was applied to two C-ion patient cases, showing predictions in line with other two models currently applied in clinics (LEM I and MKM). This work thus suggests that BIANCA can be used to predict RBE for hadron therapy