Radiobiology 2016

1/03/2016

Retreatment skin and oral mucosa • Rapid proliferative recovery begins within 2 weeks • Full re-irradiation tolerance for early injury is reached within 2-3 months • Re-irradiation tolerance for late damage will be less (cfr. slides mouse limb)

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Bone marrow • Toxicity of initial treatment must be considered, independently of blood cell counts that may be misleading! Earlier recovery of peripheral cell number does not reflect recovery of stem cell population ( i.e. restoration of radiation tolerance)

peripheral cells

peripheral cells

stimulated transit proliferation

stimulated transit proliferation

stem cells

stem cells

relative cell number

relative cell number

time

high dose/toxicity

time

low dose/toxicity

Courtesy W Dörr; Basic Clinical Radiobiology, 4th Ed, page 262

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