Brain and Spine: Dose Painting /Conformal A id /T h i lAd ... - ASTRO
Brain and Spine: Dose Painting /Conformal A id /T h i lAd ... - ASTRO
Brain and Spine: Dose Painting /Conformal A id /T h i lAd ... - ASTRO
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<strong>Brain</strong> <strong>and</strong> <strong>Spine</strong>: p<br />
<strong>Dose</strong> <strong>Painting</strong> /<strong>Conformal</strong><br />
AAvo<strong>id</strong>ance/Technical <strong>id</strong> /T h i <strong>lAd</strong> Advances<br />
John H. Suh, , M.D.<br />
Clevel<strong>and</strong> Clinic<br />
Department of Radiation Oncology<br />
Taussig Cancer Institute
Conflict of Interest<br />
• Abbott Oncology Consultant<br />
• Varian Travel grant
Objectives<br />
• Review the technical advances in radiation<br />
oncology that have allowed optimization of<br />
radiation delivery y for brain <strong>and</strong> spine p tumors.<br />
• Discuss methods to direct dose to the tumor<br />
while minimizing dose to the normal neural<br />
tissues.<br />
• Review ongoing RTOG studies that incorporate<br />
dose painting <strong>and</strong> conformal avo<strong>id</strong>ance
Radiation Therapy in 1990s
<strong>Dose</strong> distribution for spine tumors
<strong>Dose</strong> distribution for WBRT
Transmitted<br />
BBeamlets l t<br />
Intensity Modulated<br />
Radiotherapy (IMRT)<br />
Intensity<br />
Modulator<br />
Desired <strong>Dose</strong><br />
Actual <strong>Dose</strong><br />
Di Distribution t ib ti<br />
Distribution
Importance of optimizing image performance to<br />
achieve fundamental objectives of radiation therapy<br />
Dawson LA et al. The Oncologist 15:338-349, 2010
RADIATION ONCOLOGY<br />
Transition to Image g Gu<strong>id</strong>ance<br />
Elekta Synergy y gy
CRANIAL PATIENT POSITIONING<br />
ExacTrac CBCT
Therapeutic p Index<br />
Control<br />
<strong>Dose</strong> (Gy)<br />
Complications<br />
95002052 95002052-01 01
<strong>Dose</strong> painting Galvin JM, et al. J Clin Oncol 2007
Ling CC et al al. IJROBP 47:551-560 47:551 560, 2000
Stereotactic Radiosurgery<br />
“Replace the needle by narrow<br />
bbeams of fradiation di i energy <strong>and</strong> d<br />
thereby produce a local destruction<br />
of the tissue”<br />
Lars Leksell<br />
The stereotaxic method <strong>and</strong> radiosurgery<br />
of the brain<br />
Acta Chirurgica Sc<strong>and</strong>inavia Vol 102, Fasc<br />
4, 1952
Early days of Stereotactic Radiosurgery
Plugging helmets to shape dose
Different radiosurgery units
Different linac approaches for brain SRS<br />
Circular Arc<br />
IMRT<br />
<strong>Conformal</strong> Beam<br />
Hybr<strong>id</strong>Arc<br />
Dynamic <strong>Conformal</strong> Arc
Leksell Gamma Knife C<br />
Leksell Gamma Knife ®<br />
Treatable volume<br />
Leksell Gamma Knife PERFEXION
Collimator system 8-16-8-16- Collimator system 8-16-8-<br />
16 16-16-16-16 16 16 16<br />
16 16-8-16-8-16<br />
8 16 8 16
Treatment plan with composite shots
Loose frame: mismatch between MR <strong>and</strong> CT images
Preop MRI brain T1 w/ Gd
<strong>Dose</strong> Constraints for RTOG 0825<br />
• Lenses 7Gy 7 Gy<br />
• Retina 50 Gy<br />
• OOptic i nerves 55 GGy<br />
• Optic chiasm 56 Gy<br />
• <strong>Brain</strong>stem 60 Gy
RTOG 0825
53 53.0 0<br />
50.4<br />
45.0<br />
30.0<br />
10.0<br />
Sequential Planning<br />
Phase I
Sequential Planning<br />
9.3<br />
9.0<br />
7.0 Phase II<br />
3.0
Sequential Planning<br />
63.0<br />
59.4<br />
45.0<br />
45.0 Composite p<br />
30.0
Sequential Planning<br />
Six static IMRT<br />
beams were used<br />
with 3 non-planar<br />
beams.<br />
The beam was on for<br />
11 minutes.<br />
i
Simultaneous Integrated Boost<br />
63 63.0 0<br />
59.4<br />
45.0<br />
45.0<br />
30.0
Simultaneous Integrated Boost<br />
Delivery l<br />
Four partial arcs are used<br />
for the plan.<br />
Estimated beam<br />
time was about 4 minutes
Conventional Co e t o a <strong>Dose</strong> ose <strong>Painting</strong> a t g<br />
63.0<br />
59.4<br />
50.4<br />
45.0<br />
30.0
RTOG 0933<br />
Phase II Trial of Hippocampal pp p Avo<strong>id</strong>ance During g Whole<br />
<strong>Brain</strong> Radiotherapy for brain metastases<br />
• Fused planning MRI CT<br />
Fused planning MRI CT<br />
image set<br />
• Hippocampal avo<strong>id</strong>ance<br />
regions will 3D expansion of<br />
hippocampal contours by 5<br />
mm.
Beam arrangement for meningioma
Coronal isodose distribution
T1 MRI C 11 Methionine PET<br />
LLee et t al, l IInt t J Radiat R di t OOncol l Bi Biol l Phys Ph 73(2):479-85, 73(2) 479 85 2009
Patient Immobilization
50%<br />
Spinal Cord Radiation Exposure<br />
10%<br />
20%<br />
90%<br />
(a)<br />
B<br />
C<br />
A<br />
(b)<br />
20%<br />
50%<br />
90%
Modern: 16-18 Gy x1 SBRS to squamous cell met T6<br />
using 6 MV <strong>and</strong> 7 coplanar IMRT beams<br />
Conventional: Renal cell spine met treated to 30 Gy/10 fx T10-L2<br />
with AP/PA fields using g 18 MV pphotons
Spinal SBRT
Hybr<strong>id</strong> Arc Approach
RTOG 0631<br />
Phase II/III Study of Image-Gu<strong>id</strong>ed<br />
Image Gu<strong>id</strong>ed<br />
Radiosurgery/SBRT<br />
ffor Localized l d <strong>Spine</strong> Metastasis
Sol<strong>id</strong> black<br />
represents<br />
the tumor<br />
RTOG 0631<br />
Treatment Planning/Target Volumes<br />
Target volume<br />
iincludes l d vertebral t b l<br />
body <strong>and</strong> both<br />
pedicles<br />
Metastatic lesions Target volume<br />
Diagram of <strong>Spine</strong> Metastasis can be more extensive includes spinous<br />
<strong>and</strong> Target Volume including pedicles process <strong>and</strong> laminae
RTOG 0631<br />
Treatment Planning/Target Volumes<br />
Target<br />
spine<br />
Defining Partial Spinal Cord Volume<br />
Partial spinal<br />
cord<br />
5-6 mm<br />
5-6 mm
RTOG 0631<br />
Treatment Planning/Target Volumes<br />
– Threecorddoseconstraintsareusedinthisstudy<br />
Three cord dose constraints are used in this study<br />
• Constraints for partial spinal cord is 10 Gy<br />
• Constraints for conventional spinal cord is 10 Gy<br />
• Maximum cord dose is 14 Gy for less than 0.3 cc
RTOG 0631<br />
Treatment Planning/Target Volumes
Radiobiology of Radiosurgery<br />
Balagamwala E, E Chao S, S Suh J. J Tech Ca Res Treat 11:3 11:3-13, 13 2012
Conclusions<br />
• Technical advances in radiation oncology gy have allowed<br />
optimization of radiation delivery for brain <strong>and</strong> spine<br />
tumors.<br />
• <strong>Dose</strong> painting, dose sculpting, <strong>and</strong> conformal<br />
avo<strong>id</strong>ance can be achieved given the advances in<br />
ttechnology, h l iimaging i <strong>and</strong> d ttreatment t tplanning. l i<br />
• RTOG 0933 <strong>and</strong> RTOG 0631 are evaluating dose<br />
painting painting, dose sculpting sculpting, <strong>and</strong> conformal avo<strong>id</strong>ance avo<strong>id</strong>ance.