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ESTRO IMRT course 2015
Adaptive Radiotherapy
Brussels October 8th, 2015
-39-
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.