IMRT

RECTUM late rectal bleeding DVH + clinical risk factors (abdom. surgery)

LKB

TD50 (Gy) 81 (75-90)

m

n

Observed

0.14 (0.11-0.19)

0.13 (0.04-0.25)

w/o previous abd. surgery with previous abd. surgery

85 (78-96)

0.14 (0.11-0.19)

0.11 (0.02-0.23)

78 (72-89)

Including clinical risk factor: lower tolerance to radiation (also for fecal incontinence )

Peeters et al, IJROBP, 2006