Intensity-Modulated Radiation Therapy Using Serial Tomotherapy · • The Amazing The Incredible...
Transcript of Intensity-Modulated Radiation Therapy Using Serial Tomotherapy · • The Amazing The Incredible...
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IntensityIntensity--Modulated Modulated Radiation Therapy Using Radiation Therapy Using
Serial Serial TomotherapyTomotherapy
Bruce CurranBruce CurranUniversity of MichiganUniversity of Michigan
Ann Arbor, MIAnn Arbor, MI
Overview Overview
Introduction / Brief HistoryIntroduction / Brief HistoryCharacteristicsCharacteristics
Advantages / ConstraintsAdvantages / Constraints
ImplementationImplementationInstallation / CommissioningInstallation / CommissioningDaily Setup / Patient QADaily Setup / Patient QA
Clinical ResultsClinical Results
AcknowledgementsAcknowledgements
UCSF (UCSF (XiaXia et al)et al)NOMOS CorporationNOMOS CorporationWashington U (Low et al)Washington U (Low et al)Tomotherapy Inc. (Rock Mackie et al)Tomotherapy Inc. (Rock Mackie et al)
•• The Amazing The Incredible The Amazing The Incredible SuperdogSuperdogWritten by Crosby Written by Crosby BonsallBonsallPublished by HarperPublished by Harper
In the last decade, I have become increasingly concerned with tIn the last decade, I have become increasingly concerned with the rapid he rapid development of advanced radiotherapy treatment techniques. development of advanced radiotherapy treatment techniques. Unfortunately, the motivation for this expansion appears to be mUnfortunately, the motivation for this expansion appears to be market arket driven ("Come receive treatment at OUR centre, where we offer driven ("Come receive treatment at OUR centre, where we offer IMRT, etc. ..."). This U.S.IMRT, etc. ..."). This U.S.--initiated trend is now beginning to spread initiated trend is now beginning to spread to Canada and Western Europe.to Canada and Western Europe.
Can an isolated physicist at a remote clinic achieve the same coCan an isolated physicist at a remote clinic achieve the same confidence nfidence and expertise found at a larger institute? Are we not doing patand expertise found at a larger institute? Are we not doing patients a ients a disservice by employing devices and/or techniques without a totadisservice by employing devices and/or techniques without a total l understanding of their use?understanding of their use?
Jack CunninghamJack Cunningham
MedPhysMedPhys ListServerListServer Thread Thread
. . . However, after our experience with what I refer to as true. . . However, after our experience with what I refer to as trueIMRT (the binary operated collimator with multiple IMRT (the binary operated collimator with multiple independently controlled independently controlled beamletsbeamlets), I must confess that our ), I must confess that our clinical results have been extremely satisfying. Four plus clinical results have been extremely satisfying. Four plus years after treatment, we have many cases where there is no years after treatment, we have many cases where there is no sign of sign of xerostomiaxerostomia or or tumourtumour recurrence. The patients are recurrence. The patients are happy, we are happy and their dentists are very happy. happy, we are happy and their dentists are very happy. Similarly with abdominal treatments. We do not observe the Similarly with abdominal treatments. We do not observe the typical bowel complications. Again the patients are much typical bowel complications. Again the patients are much happier and so of course are we. . . .happier and so of course are we. . . .
Darrell O. PooleDarrell O. Poole
MedPhysMedPhys ListServerListServer ThreadThread Brief History Brief History
Early Theoretical WorkEarly Theoretical WorkBrahmeBrahme ((RadiotherRadiother. . OncolOncol. 12, 1988). 12, 1988)BortfeldBortfeld (Phys. Med. Biol. 35, 1990)(Phys. Med. Biol. 35, 1990)
Initial DevelopmentInitial DevelopmentSwerdloffSwerdloff, Holmes, Mackie (U , Holmes, Mackie (U WiscWisc))Carol, Campbell, Carol, Campbell, ScherchScherch (NOMOS Corp)(NOMOS Corp)
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Brief History Brief History
Initial Clinical ImplementationInitial Clinical ImplementationGrant, Butler (TMH / Baylor)Grant, Butler (TMH / Baylor)Tsai, Curran, Tsai, Curran, WazerWazer (NEMC / Tufts)(NEMC / Tufts)Low, Low, MuticMutic, , ChaoChao (MIR / Washington U)(MIR / Washington U)
Current StateCurrent State~120 Clinical Systems in Use (10,000 patients)~120 Clinical Systems in Use (10,000 patients)~15 Helical Tomotherapy Systems in process~15 Helical Tomotherapy Systems in process
What is Serial What is Serial TomotherapyTomotherapy??
INTENSITY-MODULATED RADIOTHERAPY:CURRENT STATUS AND ISSUES OF INTEREST
Intensity Modulated Radiation Therapy Collaborative Working GroupInt. J. Radiation Oncology Biol. Phys., Vol. 51, No. 4, pp. 880–914, 2001
Tomotherapy: The delivery of intensity modulated rotating fan beams. • Serial tomotherapy is the delivery of multiple fan
beams with discrete table increments between each axial gantry arc.
• Helical tomotherapy makes use of helical CT type motions (continuous synchronized gantry and table motion).
IntensityIntensity--Modulated TreatmentModulated Treatment
Tomotherapy DeliveryTomotherapy Delivery
Courtesy, NOMOS Corporation
Tomotherapy DeliveryTomotherapy Delivery
Courtesy, NOMOS Corporation
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Tomotherapy DeliveryTomotherapy Delivery
Courtesy, NOMOS Corporation
Serial TomotherapySerial Tomotherapy
Courtesy, West Penn Hospital
Why Use Tomotherapy?Why Use Tomotherapy?
Allows large search space of possible Allows large search space of possible beamletsbeamlets55/27 beam positions per 29055/27 beam positions per 290°° arc (5arc (5°° or 10or 10°° steps)steps)20 20 beamletsbeamlets per position (1,100 per position (1,100 beamletsbeamlets/arc)/arc)11 intensity levels for each 11 intensity levels for each beamletbeamlet (0 (0 –– 100%)100%)
Large gantry angle space for finding tangentsLarge gantry angle space for finding tangentsEfficient delivery with complex modulationEfficient delivery with complex modulation
Modulation complexity does not affect MUModulation complexity does not affect MU
Clinical Comparisons Clinical Comparisons –– II II
Brain tumor Brain tumor -- GBMGBM75 y.o. Asian female w. dizziness, weakness and gait 75 y.o. Asian female w. dizziness, weakness and gait disturbancedisturbanceLeft Left cerebellarcerebellar mass on MRI and CTmass on MRI and CT--guided biopsyguided biopsy
Dose constraints:Dose constraints:60 60 GyGy to GTVto GTV45 45 GyGy max to BS and optic chiasmmax to BS and optic chiasm
Plan comparisons:Plan comparisons:3 3 fldfld nonnon--coplanar 3D plan (Pinnacle) vs. coplanar 3D plan (Pinnacle) vs. IMRTIMRT-- MIMiC (Corvus) vs. MIMiC (Corvus) vs. 5 5 fldfld MLCMLC--IMRT (Corvus)IMRT (Corvus)
Courtesy, UCSF
3D-CRT IMRT-MIMiC
60 Gy, 45 Gy, 30 Gy
IMRT-MLC
Courtesy, UCSF
3D-CRT IMRT-MIMiC
60 Gy, 45 Gy, 30 Gy
IMRT-MLC
Courtesy, UCSF
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3D-CRT IMRT-MIMiC
60 Gy, 45 Gy, 30 Gy
IMRT-MLC
Courtesy, UCSF
3D-CRT IMRT-MIMiC
60 Gy, 45 Gy, 30Gy
IMRT-MLC
Courtesy, UCSF
3D-CRT IMRT-MIMiC
60 Gy, 45 Gy, 30 Gy
IMRT-MLC
Courtesy, UCSF ASO
RPOLPO
Courtesy, UCSF
LAO LAT
LPO RPO
AP
Courtesy, UCSF
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ChiasmChiasm/3dChiasm/IMRT
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GTV/IMRT
Courtesy, UCSF
Comparison Results Comparison Results –– II II Brain Brain
Much reduced dose to brainstem for IMRT Much reduced dose to brainstem for IMRT compared to 3D (MIMiC better than MLCcompared to 3D (MIMiC better than MLC--IMRT)IMRT)
dosedose--limiting structure for this tumorlimiting structure for this tumor
IMRT plans more conformal than 3D with less IMRT plans more conformal than 3D with less dose to brain outside GTVdose to brain outside GTV
could be particularly important for pediatric could be particularly important for pediatric patientspatients
Courtesy, UCSF
ConclusionsConclusions
• In general, MIMiC Plans are more conformal than MLC-IMRT plans.
• Requirement in patient immobilization for MIMiC treatment is more stringent, especially for intra-treatment movement.
• Couch index error can produce significant dose error and rigorous QA procedure is necessary.
Courtesy, UCSF
TomotherapyTomotherapy Delivery ExampleDelivery Example
Courtesy, Rock Mackie
Tomotherapy ConstraintsTomotherapy Constraints
•• Rotational Speed AccuracyRotational Speed Accuracy•• MU/Degree AccuracyMU/Degree Accuracy•• Slice Indexing AccuracySlice Indexing Accuracy•• Whole Body Dose / ShieldingWhole Body Dose / Shielding•• ImmobilizationImmobilization•• Delivery TimeDelivery Time
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Tomotherapy ConstraintsTomotherapy Constraints
•• Rotational Speed AccuracyRotational Speed Accuracy•• MU/Degree AccuracyMU/Degree Accuracy•• Slice Indexing AccuracySlice Indexing Accuracy•• Whole Body Dose / ShieldingWhole Body Dose / Shielding•• ImmobilizationImmobilization•• Delivery TimeDelivery Time
Tomotherapy ConstraintsTomotherapy Constraints
•• Rotational Speed AccuracyRotational Speed Accuracy•• MU/Degree AccuracyMU/Degree Accuracy•• Slice Indexing AccuracySlice Indexing Accuracy•• Whole Body Dose / ShieldingWhole Body Dose / Shielding•• ImmobilizationImmobilization•• Delivery TimeDelivery Time
2% / 0.1mm Accuracy Requirement (Low et al)
Tomotherapy ConstraintsTomotherapy Constraints
•• Rotational Speed AccuracyRotational Speed Accuracy•• MU/Degree AccuracyMU/Degree Accuracy•• Slice Indexing AccuracySlice Indexing Accuracy•• Whole Body Dose / ShieldingWhole Body Dose / Shielding•• ImmobilizationImmobilization•• Delivery TimeDelivery Time
The head and wholeThe head and whole--body phantom used to body phantom used to measure the wholemeasure the whole--body dose databody dose data
Courtesy, Wash U of St. Louis
Scatter and leakage dose distribution along Scatter and leakage dose distribution along the gantry axis of rotationthe gantry axis of rotation
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Internal Scatter and LeakageLeakage Alone
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Z (mm)Courtesy, Wash U of St. Louis
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WholeWhole--body dose equivalent (40 cm from field body dose equivalent (40 cm from field edge): 70 edge): 70 GyGy target dosetarget dose
FollowillFollowill et al.et al. -- 543 543 mSvmSv -- Three arcs, 20 X 20 cm Three arcs, 20 X 20 cm 22 fixed fixed beam data, and 3.24 MU cGybeam data, and 3.24 MU cGy--11 per arcper arcOur calculation Our calculation -- 315 315 mSvmSv -- Five arcs, 10 X 10 cm Five arcs, 10 X 10 cm 22 fixed fixed beam data, and 1.8 MU cGybeam data, and 1.8 MU cGy--11 per arcper arcOur measurements Our measurements -- 271 271 mSv mSv
Courtesy, Wash U of St. Louis
Conclusions (Low et al) Conclusions (Low et al)
Estimated fatal secondary cancer (fatal leukemia) due to a Estimated fatal secondary cancer (fatal leukemia) due to a 70 70 GyGy course of radiation therapy:course of radiation therapy:
Conventional TherapyConventional Therapy 0.4%0.4%FollowillFollowill et al. et al. –– TomotherapyTomotherapy 2.8%2.8%Measured Measured -- TomotherapyTomotherapy 1.4%1.4%
Courtesy, Wash U of St. Louis
Tomotherapy ConstraintsTomotherapy Constraints
•• Rotational Speed AccuracyRotational Speed Accuracy•• MU/Degree AccuracyMU/Degree Accuracy•• Slice Indexing AccuracySlice Indexing Accuracy•• Whole Body Dose / ShieldingWhole Body Dose / Shielding•• ImmobilizationImmobilization•• Delivery TimeDelivery Time 0 Minutes 15 Minutes later 30 Minutes later
Three Sets of Orthogonal FilmsThree Sets of Orthogonal Films
Courtesy, UCSF
0 Minutes 15 Minutes later 30 Minutes later
Three Sets of Orthogonal FilmsThree Sets of Orthogonal Films
Courtesy, UCSF
Tomotherapy ConstraintsTomotherapy Constraints
•• Rotational Speed AccuracyRotational Speed Accuracy•• MU/Degree AccuracyMU/Degree Accuracy•• Slice Indexing AccuracySlice Indexing Accuracy•• Whole Body Dose / ShieldingWhole Body Dose / Shielding•• ImmobilizationImmobilization•• Delivery TimeDelivery Time
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Delivery Time IssuesDelivery Time Issues
Accurate IndexingAccurate IndexingMultiple Rotations / TreatmentMultiple Rotations / TreatmentDose RateDose RateMU EfficiencyMU Efficiency
Courtesy, NOMOS Corporation
Implementation of Serial Implementation of Serial TomotherapyTomotherapy
Currently available from a single vendorCurrently available from a single vendorNOMOS Corporation, Cranberry NOMOS Corporation, Cranberry TwnshpTwnshp, PA, PA
Courtesy, NOMOS Corporation
Courtesy, NOMOS Corporation
Installation / CommissioningInstallation / Commissioning
Mechanical InstallationMechanical InstallationPower & Air Cabling through gantryPower & Air Cabling through gantryTable indexing apparatusTable indexing apparatusMIMiCMIMiC Alignment pins / attachmentAlignment pins / attachment
CommissioningCommissioningAlignmentAlignmentIndex determinationIndex determination
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Radial Alignment Film(90 / 270 gantry angle w/ film 15cm off isocenter
Transverse Alignment Film(90 / 270 checkerboard w/ film at isocenter
Alignment FilmsAlignment Films Indexing Test Indexing Test
Serial Serial TomotherapyTomotherapy ExampleExample
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University of Texas Health Science Center / Cancer Therapy and Research Center (CTRC)San Antonio, Texas
University of Texas Health Science Center / Cancer Therapy and Research Center (CTRC)San Antonio, Texas
1998
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University of Texas Health Science Center / Cancer Therapy and Research Center (CTRC)San Antonio, Texas
Clinical CasesClinical Cases
Tomotherapy MLC
Tomotherapy MLCCraniopharyngioma encompassing the optic chiasm
Acoustic neuroma adjacent to brain stem
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Mediastinal mass with sparing of bronchus
Meningioma with sparing of optic nerve
Thank youThank you
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