Gynae BT 2017

Inter-fraction motion of CTV-N TV-T – In er al Target Volume

Nodes also move! (a little)

• 48 nodes, 15 patients, repeat MRI during EBRT • Position shift in 6 directions assessed • Affected nodes also change their position • Order of magnitude lower than for primary GTV (< 10 mm)

Maximal margins (computer)

9

8

7

6

5

4

3 margin (ml)

2

1

0

med

lat

ant

post

sup

inf

Schippers M, et al. 2011