2017_SBRT_Course Book

Spinal cord tolerance – reirradiation: Animal studies

„Optimistic“ model

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

„Pessimistic“ model

ESTRO SBRT 2017 - Matthias Guckenberger

07.09.17

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Spinal cord tolerance – reirradiation: Animal studies

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

ESTRO SBRT 2017 - Matthias Guckenberger

07.09.17

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