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IMRT & GI toxicity
- But….negative report from a controlled trial,
WHY ?
- Constraints V35<180 cc; V40<100 cc; V45<65 cc ?...they used «peritoneal
space» as «small bowel» contour
- No sparing on V15-V20 ? (no !, they tested: V10-V45 not correlated..)
- Little portion of bowel to be spared compared to 3DCRT ?
- Major contribution from CHT and from rectum irradiation ?
- It is a question of CTV/PTV volumes ?
- Hot spots permitted in the PTV (V115%<5%) & no constraints on bowel
>V45/Dmax
………….Good to discuss bowel constraints….come back later !