ESTRO course on Image Guided Radiotherapy in Clinical Practice 2018

1: Day to day, random changes

Cervix cancer, classical approach

 Uterus motion: large and depending on bladder filling  Cervix motion: smaller and depending on rectal filling  Margin proposals:  Taylor: 15, 15 and 7 mm  Chan et al:  (90% of the fractions within the PTV)  40 mm at fundus (top of uterus)  15 mm at cervix

 Cervix  Bladder

 90% for intrafraction (30 minutes) only:  10 and 5 mm

Radiotherapy

Radiotherapy

Example of target inside PTV “non-mover”

Example of target outside PTV “mover”

CT and CBCT week 1-5

CT and CBCT week 1-5

Grey: Bladder

Grey: Bladder

Black: CTV combined

Black: CTV combined

White: - PTVuterus (CT)

White: - PTVuterus (CT)

- PTVcervix (CT)

- PTVcervix (CT)

Radiotherapy

Radiotherapy

Courtesy Peter de Ruyter and Monique Bloemers

Courtesy Peter de Ruyter and Monique Bloemers

Still the most determining aspect of IGRT!

Cervix plan of the day made easy

1 PTV

Cervix: back to the basics: The Target

2 PTV’s

3 PTV’s

•Bondar et al IJROBP 2011

Radiotherapy

Radiotherapy

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