ESTRO course on Image Guided Radiotherapy in Clinical Practice 2018

Adaptive RT in Head and Neck

Planning

No adaptation

With adaptation

 15 patients with advanced HN cancer  70 Gy 7 weeks  Weekly repeat CT  Results:  4 Gy more mean dose to the parotid than planned without adaptation  5 Gy less mean dose to the parotid gland with weekly replanning compared to no adaptation

This is what you can make of it

This is what you think you get

This is what you get

Castelli 2015

Castelli 2015

Radiotherapy

Radiotherapy

Summary: ART for head and neck

3: Art for (Un) expected changes

 Careful when adapting for tumor shrinkage  You can overcome the deleterious effect of parotid gland shrinkage on parotid dose  One adaptation dose most of the tric  You do not need deformable registration:  if the individual plans are safe the summation is also safe

 Lung cancer, tumor regression (?), atelectasis (either appearing or dissolving)  Cervix, void of hematocolpos (Uterus with blood)

Radiotherapy

Radiotherapy

ART for (un-)expected changes

• New situation during treatment

 Lung cancer and atelectasis  Rianne demonstrated the traffic light warning system (i.e. guidelines on what to do with an image finding at the treatment machine)

Radiotherapy

Radiotherapy

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