2017_IGRT course book

CTV to PTV margins with respect to IGRT practice: a survey of RO in the US

Treatment site

First few fractions

weekly

daily

Head and Neck

5 mm

4.9 mm

4.8 mm

Lung

6.4

6.6

6.2

Prostate IMRT

4.9

4.5

4.6

Nabavizadeh et al IJROBP 2015 (showing only data for CBCT)

Survey shows that margins are more dependent on the physician than on imaging type/frequency