1、螺旋断层放疗Tomo的技术特征和临床价值,螺旋断层放疗的技术特征与临床价值,Dr Mesh Meta：全球第一位使用TOMO的放疗科主任,What is Tomo Really Good At?,Daily Image GuidanceVery large field set-upsCraniospinal, whole abdomen, TMIMultiple lesions/prescriptionsBrain, bone, othersH/N multiple prescriptionsComplicated geometries and set-upsMesothelioma, ret
2、reatments, AvoidanceExploiting radiobiologyAltered fractionation, SBRT, TheragnosticsAdaptive radiotherapy,+,+,Fast Binary MLC(Multileaf Collimator),Continuous Gantry Rotation,Simultaneous Couch Movement,高调制,The Key Technology of Helical TomoTherapy,多角度,长覆盖,Modulated beams throughout one 360 degree
3、rotation.The process continues for all rotations,Binary MLC,Intensity levels in one modulated beam,One beamlet within the beam,Modulated Beam Delivery,Helically Delivered Dose Distributions,What is Tomo Really Good At?,Daily Image GuidanceVery large field set-upsCraniospinal, whole abdomen, TMIMulti
4、ple lesions/prescriptionsBrain, bone, othersH/N multiple prescriptionsComplicated geometries and set-upsMesothelioma, retreatments, AvoidanceExploiting radiobiologyAltered fractionation, SBRT, TheragnosticsAdaptive radiotherapy,Image Guidance via Image Fusion,Colored segments = MVCTGrey segments = p
5、lanning CT,Repositioning Shifts After Image-Guidance on Tomotherapy,A Statistical Analysis of H&N, Lung, and Prostate Treatment Sites,Leah Kamin, University of Wisconsin,What is Tomo Really Good At?,Daily Image GuidanceVery large field set-upsCraniospinal, whole abdomen, TMIMultiple lesions/prescrip
6、tionsBrain, bone, othersH/N multiple prescriptionsComplicated geometries and set-upsMesothelioma, retreatments, AvoidanceExploiting radiobiologyAltered fractionation, SBRT, TheragnosticsAdaptive radiotherapy,Craniospinal Axis Treatment,Patient treated supine with no field junctions,Conventional Lina
7、c,Courtesy of Willis-Knighton Cancer CenterShreveport, LA,Helical TomoTherapy,Patient treated prone with two field junctions,“Magna-Field Radiotherapy”,Whole Abdomen,City of Hope: TMI,Pelvic/para aortic nodal,What is Tomo Really Good At?,Daily Image GuidanceVery large field set-upsCraniospinal, whol
8、e abdomen, TMIMultiple lesions/prescriptionsBrain, bone, othersH/N multiple prescriptionsComplicated geometries and set-upsMesothelioma, retreatments, AvoidanceExploiting radiobiologyAltered fractionation, SBRT, TheragnosticsAdaptive radiotherapy,Courtesy Minesh Mehta & Emiliee Soisson, University o
9、f Wisconsin,Multiple Targets in Single Setup,PTV,Hippocampus,SolidHomogeneous,DashedGradient,Multiple Targets in Single Setup,Multiple Bone Mets,Multiple Prescriptions,Head and Neck,Multiple Prescriptions,Prostate and Nodes,What is Tomo Really Good At?,Daily Image GuidanceVery large field set-upsCra
10、niospinal, whole abdomen, TMIMultiple lesions/prescriptionsBrain, bone, othersH/N multiple prescriptionsComplicated geometries and set-upsMesothelioma, retreatments, avoidanceExploiting radiobiologyAltered fractionation, SBRT, TheragnosticsAdaptive radiotherapy,Avoiding the hippocampus,Helical Deliv
11、eryBinary MLC / 6.25 mm leavesConformity index: 1.35 Dose gradient: 3.59%/mm,7-field IMRT3 mm MLC leavesConformity index: 1.82Dose gradient: 2.96%/mm,City of Hope National Medical Center,Avoiding the chiasm/pit gland,Avoiding anything, really!,What is Tomo Really Good At?,Daily Image GuidanceVery la
12、rge field set-upsCraniospinal, whole abdomen, TMIMultiple lesions/prescriptionsBrain, bone, othersH/N multiple prescriptionsComplicated geometries and set-upsMesothelioma, retreatments, avoidanceExploiting radiobiologyAltered fractionation, SBRT, TheragnosticsAdaptive radiotherapy,NSCLC: Overcoming
13、Accelerated Repopulation,Fowler JF, Chappell R, IJROBP, 2000; Mehta MP, Fowler, IJROBP 2001; Belani C, Mehta M, JCO, 2005; Adkison, Mehta: TCRT, 2008,2000: Evidence for accelerated repopulation in NSCLC2001: TDF method to overcome resistance2005: Evidence for benefit of accelerated RT2008: Accelerat
14、ed HT with low toxicities, ? survival improvement,Lower than Expected Toxicities; Survival Improved?,No Chemo 43%, Neoadjuvant 24%, Adjuvant 33%,As Compared to 21.5%Expected Two Year Survival,Stereotactic Body Radiotherapy with 4D IM-IGRT,Hodge W, Mehta MP. Acta Oncol. 2006;45:890-6,N = 23, in press
15、,88% 4 Y LC,78% 4 Y CSS,Prostate: Exploiting / (Fractional Sensitivity),Fowler JF, Ritter M, IJROBP, 2001,2000: Rectal balloon immobilization technique2001: Data Analysis for low prostate / 2002: Prostate Hypofx PO1 protocol2004: Prostate Hypofx multi-institutional RO12009: Initial data analysis,Pro
16、state: Keeping Toxicities Low,Tomotherapy SRS: AVM as a Model,Rt. Occipital AVMVol = 5.01cc2+ hours planning time11 isocenters4 collimator changes3+ hours on the table,Pinnacle-Thick SolidMatch-Dashed,Original Plan,Match,Soisson E, Tome W, Mehta MP, U Wisconsin,Tomos Choice,Original Plan,Choice,Orig
17、inal Plan,Match,VolRx = Volume of target receiving prescriptionTC = Target Coverage VolRx/TVHI= Max Dose/RxPITV=PIV/TVCI = VolRx/PIVCN= 1/(CI x TC),What is Tomo Really Good At?,Daily Image GuidanceVery large field set-upsCraniospinal, whole abdomen, TMIMultiple lesions/prescriptionsBrain, bone, othe
18、rsH/N multiple prescriptionsComplicated geometries and set-upsMesothelioma, retreatments, avoidanceExploiting radiobiologyAltered fractionation, SBRT, TheragnosticsAdaptive radiotherapy,Adaptive Radiotherapy,Week 1,Week 3,Calculate daily doses,Modify original contours,Map hot dose levels,Contour hot
19、 spot and make it a constraint,Adaptive Radiotherapy,Pre-RT KvCT; intra-RT MvCT,SCLC after 18 Gy,+,+,Discrete Beam Angles,Continuous Couch Motion,=,Moving Couch,Fast Binary MLC(Multileaf Collimator),TomoDirect,WBRT,Multiple lesions,Efficient, IMRT, accuratesimple fields e.g. Tangents,TomoDirect + To
20、mo: The Breast Solution,Dynamic Jaw Saves Time: Whole Abdominal RT,treatment time regular 2.5cm 17 minutes, dose penumbra!,djdc 5cm: 5.5 minutes, minimized penumbra,Heidelberg,The Next Frontier: Theragnostic XRT,Basic premise: Deliver non-homogenous RT doses to different tumor sub-volumes, based on
21、an analysis of local control probability derived from predictive functional imaging difference maps early in treatment.The ultimate in “personalized XRT”,Generate a baseline agnostic plan,Obtain baseline and early in-treatment functional imaging,Correlate maps with eventual outcome,Develop a prescription model,Test the model in a theragnostic dose-painting trial,Dose Painting: Feasibility Studies,IMRT: HT Dose Painting,IMPT (Spot Scan) Dose Painting,Early treatment planning results confirm that we can deliverNon-homogenous doses that mimic functional imaging maps,Thank You,
