ATP Barcelona 2017

Conclusions • QA of deformable image registration is complex

• Deformable image registrations is unsolved problem; algorithms lack biological and biomechanical knowledge • Sliding tissue • Tumor growth and regression • This is OK to make pretty pictures and propagate OAR contours • This is not OK for dose accumulation: it is unsafe to estimate you know where previous dose went • This is not OK for adaptation around ‘shrinking’ tumors • I therefore strongly suggest no to optimize dose on top of ‘accumulated’ dose