IMRT

Dose-volume constraints for IMRT: bladder

 Less radiosensitive as compared to small bowel 

e.g. primary RT gynaecological/urological malignancies (often doses > 70Gy)

 Sauer et al: only 2% grade 3+ late GU toxicity  Appelt et al. (n=345, preoperative long-course chemoRT):  first report on dose-volume relationship for acute urinary toxicity in rectal cancer

 No clinically significant benefit is to be expected from IMRT with regard to GU toxicity

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