Has radiotherapy the potential being focal?

Size: px

Start display at page:

Download "Has radiotherapy the potential being focal?"

Bethany Austin
6 years ago
Views:

1 Has radiotherapy the potential being focal? György Kovács & Alexander Schlaefer* Interdisciplinary Brachytherapy Unit and *Institute of Robotics and Cognitive Systems, University of Lübeck / 1

2 100% 90% bned Phase III Studien EBRT+HDR (Guix, Hoskin 2007) Ions (Chiba) EBRT + HDR-BT (UK-SH, Berlin/ D - WB, Seattle, CET/USA, Göteborg/S) Proton-boost (Boston / RTOG) EBRT (conv. / 3D-CRT) IMRT (MSKCC I, II) 80% 70% Radical Prostatectomy 60% 50% Dose (Gy)

3 Treatment Plan Adaptation! n Fraction By courtesy of Varian, USA

4 By courtesy of Varian, USA

6 Technical possibilities: IMRT SIB IGRT Cyber Knife Intensity Modulated RadioTherapy Simultaneous Integrated Boost Image Guided RadioTherapy Robotic Radiotherapy Interventional Radiotherapy BrachyTherapy / 6

7 IMRT Σ FDA 510(k) - Images courtesy of KFJ Hospital, Vienna Austria

8 SIB / 8

9 / 9

10 / 10

11 IGRT Match/align Marker Template with actual setup images Calculate couch motion required to correct setup FDA 510(k) Courtesy of VARIAN

12 X-ray Sources IMAGING SYSTEM Linear Accelerator ROBOTIC DELIVERY SYSTEM Typical treatment includes beams Image delivered from up to 100 or more Detectors positions around the patient, for targets located anywhere in the body Each beam can be targeted at a unique position within the target volume Courtesy of W. Kilby / Accuray

$Prescription dose 38 Gy in 4 fractions$ 5 Gy) and 150% (57Gy) Isodoses: 57, 47.

13 2) 3) Heterogeneous, Dynamic Contrast 1) Uniform HDR Enhanced brachytherapy Prostate MRI-guided Coverage type dose focal distribution irradiation Prescription dose 38 Gy in 4 fractions Peripheral zones boosted to 125% (47.5 Gy) and 150% (57Gy) Isodoses: 57, 47.5, 38, 30, 20, 10, 5Gy Courtesy of W. Kilby / Accuray

$Inter- and intra-fraction motion correction All CyberKnife System treatments are performed using continual X-ray image guidance and correction (repeating the image-align-treat cycle) All$

14 Inter- and intra-fraction motion correction All CyberKnife System treatments are performed using continual X-ray image guidance and correction (repeating the image-align-treat cycle) All translational and rotational changes are corrected (no thresholds) Maximum Image Age is adapted automatically based on observed intra-fraction motion pattern (minimum 15s) Courtesy of W. Kilby / Accuray

15 Interventional Radiotherapy (Brachytherapy) / 15

16 / 16

17 CT Basis for treatment planning (tissue density information) CT shows no zonal anatomy CT shows no tumor in prostate CT shows no T3 situation CT shows large tumor mass

18 MRI TRUS

20 Interstitial tissue separation Tom Budiharto, Karin Haustermans, Gyoergy Kovacs Journal of Endourology. May 2010, 24(5): doi: /end

21 Seattle type plan San Diego type plan / 21

22 IMRT versus BT

23 CK versus BT / 23

$Potential of different radiotherapy technology at localized prostate cancer CK IMRT IGRT BT Target Definition worse* worse* worse* better Interfraction Movements better worse better better$

24 Potential of different radiotherapy technology at localized prostate cancer CK IMRT IGRT BT Target Definition worse* worse* worse* better Interfraction Movements better worse better better Intrafraction Movements better better 4D better 4D better Target dose painting better better 4D better 4D better Low Dose Volumes worse worse worse better Dose on OAR s better worse worse better Invasivity better better better worse *better with image fusion

25 Navigation for Focal Therapy Focal therapy requires image guidance! Ideally, we could image organ deformation and tissue properties in real-time One approach could be advanced ultrasound processing (e.g., HistoScanning) Another potential approach is to develop imaging needles, e.g., for brachytherapy

26 Navigation for Prostate HDR Brachy One potential image modality is Optical Coherence Tomography (OCT) Allows for high temporal (> 1200 A-Scans / s) and spatial (10 µm) resolution Could be integrated into a needle to get high-resolution images from inside the prostate / 26

27 Navigation for Prostate HDR BrachyTx Precisely moved needles (e.g., using a robotic needle driver) could be used to study local tissue properties Aditionaly, forces during insertion can be measured to compensate defomation / 27

28 Navigation for Prostate HDR BrachyTx OCT images and force data could augment ultrasound images to better target the dose distribution to tumor foci US image / 28

29 Has radiotherapy the potential being focal? YES! IF WE KNOW WHERE TO SHOOT / 29

30 However, the best method is not yet defind. / 30

Jean Pouliot, PhD Professor and Vice Chair, Department of Radiation Oncology, Director of Physics Division

IMRT / Tomo / VMAT / Cyberknife / HDR Brachytherapy: Jean Pouliot, PhD Professor and Vice Chair, Department of Radiation Oncology, Director of Physics Division Should Choices be Based on Dosimetric and