Table 3.

Dose constraints for organs at risk for stereotactic body radiotherapy in 5 fractions (experimental arm). PRV-Rectum_adapt is created by 2 mm isotropic expansion of Rectum_adapt. Rectum_adapt will be generated by delineation of the rectum in the co-registered CB-CTs, MV-CTs or MRI images of the first three fractions. Manual delineation of the Rectum_adapt should consider the mean rectal volume.

OAR	Constraint
PRV-Rectum or PRV-Rectum adapt	D0.03cc (near Dmax): <38 Gy (minor deviation: 38–40 Gy)
Rectum	D1cc: <36 Gy (minor deviation: 36–38 Gy)
	D2cc: <35 Gy
	D20%: ≤28 Gy
PRV-Urethra	D0.01cc (near Dmax): <40 Gy (minor deviation: 40–42 Gy)
Urethra	D50%: <36 Gy (minor deviation: 36–39 Gy)
Bladder	D0.03cc: <38.06 Gy (minor deviation: 38.06–40 Gy)
	D5cc: <37 Gy
	D15%: ≤32 Gy:
	D20%: ≤28 Gy
	D50%: <18.12 Gy (minor deviation: 18.12–20 Gy)
Penile bulb (facultative)	D90%: ≤20 Gy
	D50%: ≤29.5 Gy
Femoral head (left or right)	D5%: ≤28 Gy
Small bowel	D < 5cc: 18.1 Gy
	D0.01cc (near Dmax): <30 Gy (minor deviation: 30–33 Gy)