1258 / 1578
/
Spinal cord tolerance – reirradiation:
Animal studies
56 Rhesus monkeys, SFD 2.2Gy to 44Gy
Reirradiation
• 57.2Gy after 1 and 2 years
• 66Gy after 2 and 3 years
Ø
4 / 45 animals developed RMP
Optimistic model:
Ø
Recovery of 76%, 85% and 101%
after 1, 2 and 3 years
Conservative model:
Ø
Recovery of 61%
Ang IJROBP 2001
„Optimistic“ model
„Pessimistic“ model
ESTRO SBRT 2017 - Matthias Guckenberger
19
07.09.17
/
26 minipigs, uniform 30Gy in 10 Fx
Reirradiation after 1 year:
• Inhomogeneous (10-90%) SRS
• 14.9Gy – 25.4Gy
Ø
ED
50
of 19.7Gy
Ø
Identical SRS tolerance as in the
primary situation
Ø
Full recovery of 30Gy in 10 Fx within
1 year
Medin IJROBP 2011
Spinal cord tolerance – reirradiation:
Animal studies
ESTRO SBRT 2017 - Matthias Guckenberger
20
07.09.17