IMRT Course 2016

Daily rigid isocentre adaptations/IGRT: Conclusions

• Daily online adaptive concepts further reduce uncertainties, but do not remove uncertainties completely

• there is still a lower limit for margin size – treatment with ‘zero margin’ is not safe even with online imaging efforts

• too much margin reduction might be dangerous for other reasons as well: extra-capsular extension, see Chao et al. 2006 (IJROBP 65(4))

My personal opinion: Even with advanced daily IGRT possibilities, there is still a need for ‘smart’ probabilistic and robust planning approaches – beyond the margin approach – due to the remaining uncertainties.

ESTRO IMRT course 2016 Adaptive Radiotherapy London April 7th, 2016

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