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IGRT for rectal cancer
- Mesorectum reported to change
in shape (correlated mainly with
bladder and, secondarily, rectum
motion)
- Main changes in ANT direction
- Larger impact for short-course,
prone position and female pts
- Residual margins difficult to
assess (local deformations, CTV
contouring uncertainty)
- «Optimal» margins often not
clinically feasible
(Dmin>95%/90% pts too strict
criterion? Contouring uncertainty
too high..?)
- Issues concerning the real clinical
impact in neo-adjuv RT(CHT)
Njikamp 2012
Wout With daily correction