ESTRO course on Image Guided Radiotherapy in Clinical Practice 2018

ART for lung: mid-treatment adaptation

ART for lung: mid-treatment adaptation

Significant decrease of +/- 30% in tumor and target volume

Radiotherapy

Radiotherapy

ART for lung: mid-treatment adaptation

What does a smaller image of the tumor mean?

Shrinkage Dissolvement

Start

Note: Arrows point at vessels

15 patients stage III lung cancer Replanning after 44 of 66 Gy Clinical trial

Half way

Sonke et al 2010

Radiotherapy

Radiotherapy

Do you need deformable registration if you want to do adaptive radiotherapy?

In summary:

 Ask yourself what kind of adaptation you want  Act accordingly  Careful when adapting on a smaller projection of the tumor:  Would you have accepted an upfront underdosage to the microscopic part of the original CTV?

 No : if all individual plans are safe AND with adequate coverage , the summation will be safe and appropriate for the target as well

 Yes : if you want to know the actual dose to the OAR’s

Radiotherapy

Radiotherapy

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