Basic Clinical Radiobiology 2017

9/16/17

RTOG 90-03: A Phase III Trial Assessing Relative Efficacy of Altered Fractionations

R A N D O M I Z E

Stage III & IV SCC of :

1. Conventional Fractionation: 70 Gy / 35 F / 7 W 2. Hyperfractionation:

• Oral cavity • Oropharynx • Larynx • Hypopharynx

81.6 Gy / 68 F / 7 W (1.2 Gy/F) 3. Accelerated Fractionation (Split): 67.2 Gy / 42 F / 6 W (2 W Rest) 4. Accelerated Fractionation (CB): 72 Gy / 42 F / 6 W (1.8-1.5 Gy/F)

Stratify :

• No vs N+ • KPS

60-80 VS 90-100

ESTRO 2017

The “x” Rs of Radiotherapy • Radiosensitivity • Repair • Repopulation • Redistribution • Reoxygenation • iRradiated volume • Restoration (long term recovery) • Re-iRRadiation • another “R” still to be invented…

ESTRO 2017

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