ESTRO 2022 - Abstract Book

S571

Abstract book

ESTRO 2022

Results All reRT plans fulfilled D 95% ≥ 95 % and D 2% ≤ 105%. The EQD2 distributions in Fig. 2a and 2b resulted in 0.93, 0.91 and 8.54 (HI, CI, GI) using the standard functions compared with 0.95, 0.92 and 5.50 using the novel functions for scenario A. The corresponding values for scenario B were 0.90, 0.90 and 9.03 for the standard functions vs. 0.92, 0.96 and 6.81 for the novel functions, whereas for scenario C the standard functions resulted in 0.90, 0.70, 14.81 vs. 0.91, 0.98, 9.86 for the novel functions.

Conclusion The novel optimization functions were well-suited for reRT with increased HI and CI as well as reduced GI compared to standard functions for all scenarios in this proof-of-concept study. These novel functions are being tested in the Support Tool for Re-Irradiation Decisions guided by Radiobiology (STRIDeR) project and have the potential to be instrumental in the future of reRT planning.