2017_IGRT course book

Prostate adaptive RT

Planning CBCT 1..6 Mean

Mild laxation to reduce rectal gas

SIB plan (78 Gy) with 10 mm margin for first 6 fractions 6 cone beam scans Automatically detect prostate motion and delineate rectum in cone beam scans Generate prostate in mean position Generate mean rectum

Replan using mean prostate / rectum with 7 mm margin and treat remaining fractions

Results in better GTV coverage and rectum sparing (  30% less rectum NTCP)

Planning CBCT 1..6 Mean