Research Masterclass in Radiotherapy Physics 2017

Plan Library vs. Online Re-Planning

Plan library

Online re-planning

Does not require full segmentation of target volumes and organs at risk No time is lost by online (re)optimization of the plan of the day Plan library approaches can be incorporated in existing radiotherapy workflows Plans stored in the plan library can be QA’d in advance A-priori generated treatment plans do not necessarily accommodate all anatomies Tumor shrinkage is difficult to model a-priori and is therefore hard to incorporate in plan libraries

Requires full segmentation (and approval) of target volumes and organs at risk If (re)optimization time is too long intra-fractional motion will limit the precision of online adaptive approaches Daily (re)optimization requires a completely new workflow (Re)optimized plans should be QA’d on the fly

Full (re)optimization will provide the most tight- fitting treatment plan

(Re)optimization can incorporate tumor shrinkage, but is it safe?